Sponsored Content NBC News Learn is a former division of NBC News ‐ distributing the journalism and storytelling of NBC News to students in the classroom, at home, and in the community. Evolution of the Golf Ball – STEM Lesson Plan (Grades 6-12) June 10, 2020 | 28 minutes, 44 seconds read This document is a companion piece to video titled Evolution of the Golf Ball and is intended as a resource for educators. Background and Planning Information About the Video This video discusses the history and physics of golf balls, along with ongoing research and development aimed at producing optimal distance and spin properties. It features Steve Quintavalla, Ph.D. (Mechanical Engineering), Senior Research Engineer for the United States Golf Association (USGA). The video focuses on two important aspects of ball design: the aerodynamic benefits of dimples, and the tailoring of spin properties. It shows the role physics and engineering have played in improving both distance and spin control. Also, the story of the discovery of the benefits of dimples shows how serendipity and simple experience over time have suggested improvements, which science could then later explain and help optimize. Video Timeline 0:00 0:15 Series opening 0:16 0:35 Overview of changes in golf balls over time 0:36 0:57 Introducing Steve Quintavalla, who begins a timeline of golf ball evolution 0:58 1:07 Featheries 1:08 1:32 Gutties 1:33 2:12 Discovering that dimples allow longer flight, and the reason for this 2:13 2:31 Haskell balls and beginning of interior changes 2:32 2:50 Describing interior of modern golf balls 2:51 3:15 Materials and manufacturing of modern golf balls 3:16 3:54 Explaining the importance of spin, especially regarding its influence on lift 3:55 4:21 Detailing manufacturing standards for golf balls, to ensure consistent play 4:22 4:54 Testing of golf balls 4:55 5:11 Summary 5:12 5:31 Closing credits Language Support To aid those with limited English proficiency or others who need help focusing on the video, click the Transcript tab on the side of the video window, then copy and paste the text into a document for student reference. Next Generation Science Standards Consider the investigation described in Facilitate SCIENCE Inquiry section as part of a summative assessment for the following performance expectations. Refer to a NGSS document for connected Common Core State Standards for ELA/Literacy and Mathematics. Motion and Stability: Forces and Interactions MS-PS2-1. Apply Newton’s Third Law to design a solution to a problem involving the motion of two colliding objects. HS-PS2-1. Analyze data to support the claim that Newton’s second law of motion describes the mathematical relationship among the net force on a macroscopic object, its mass, and its acceleration. (page 1) Promote STEM with Video Connect to Science Science concepts illustrated in this video include aerodynamics and the effect of rough surfaces and spin on drag and lift. Students may find the idea that rougher surfaces can actually reduce drag to be counterintuitive: the phenomenon of reduced drag due to early onset of turbulent flow is a rather complex one, and requires rather high speed (such as that commonly reached by golf balls) relative to the air to become effective. Students may be assured that many things in nature do fit “common sense,” but that there are, in fact, some interesting surprises such as this one. Also, the video shows that the discovery of benefits of dimples was made serendipitously; many other scientific discoveries were made in unplanned ways as well. Related Science Concepts aerodynamics drag friction turbulent airflow mass force acceleration Newton’s Second and Third Laws Take Action with Students Use the video as a springboard to start students brainstorming examples of facts or concepts they have learned in science that “made sense” to them right away, and also examples of things that seemed to defy common sense, and were even hard to believe. Ask students where they get their idea of “common sense” and why some things that are true seem at first as if they couldn’t be. You might also ask students to think of examples of scientific discoveries that were made by accident (such as the effect of dimples, discovery of penicillin, and composition of nonstick coatings), only to be explained after the fact (if at all). Connect this idea to students’ own experiences. Ask if they have ever figured something out or noticed a better way to do something by accident. Students can also be reminded that scientific thinking involves “shopping around” for explanations that work. Explain that “common sense” ideas often are developed first and are a necessary first step. Connect to Technology Modern technology – such as devices to shoot golf balls at high speed and monitor their position, speed, and rotation in flight – is needed to analyze data and develop new designs. The USGA uses robotic golfers and a ball launcher (similar to some baseball pitching machines) to collect such data. Take Action with Students Show the portion of the video, starting at about 4:21, which shows the USGA’s Indoor Test Range. Have students discuss what types of data this facility can gather and what advantages it might have over outdoor testing or how it can be used in conjunction with outdoor testing. Have students research this test facility on the Internet. One revealing document is at http://www.usga.org/uploadedFiles/USGAHome/equipment/testing/protocols/Overall_Distance_TPX3006.pdf, which shows how carefully scientific testing must be done—with great attention to detail—in order to gather reliable data. (page 2) Connect to Engineering The engineering design process involves all of the above, plus the human ingenuity and creativity – and sometimes even simple luck – needed to bring all these facets together to produce ever-better golf balls. The history of the golf ball is a good illustration of how engineering consists not only of creating a product, but continuing to improve it as new technological and mathematical tools become available. Take Action with Students Have students choose another product that has a modern version, and yet has existed in some form for decades (such as video games or performance fabrics), or centuries (such as pen and ink), and outline that product’s history of development. Then have them compare this product’s evolutionary development to that of the golf ball, pointing out ways in which the development was similar, and ways in which it was different. Have students do research to identify other uses of gutta percha (i.e., filling root canals) and polybutadiene (i.e., tires). Ask them to explain what required properties candidate substances must have for each of these applications, and how gutta percha and polybutadiene meet these criteria. Have students suggest other applications of dimples that would enhance a feature of a product in existence. Connect to Math Math, while not discussed in detail in this video, is essential for modeling what happens to the ball during impact with the club, and what the resulting flight of the ball will be. The physical laws that describe or govern what happens when a ball is struck by a club, and how the ball interacts with the air during flight, are expressed as mathematical equations, and can be solved by humans – or, more efficiently, in computer simulations. High school students who have had algebra will likely have encountered the shape called a parabola, and the general equation that defines it. They may have also done problems in math or physics class in which they calculated the parabolic trajectory of a projectile. As a first approximation, a golf ball’s path “should” be a parabola, but the drag and lift forces acting on the ball can change this rather dramatically. Take Action with Students Have students interact with online projectile simulators such as that found at http://phet.colorado.edu/sims/projectile-motion/projectile- motion_en.html. This one includes drag forces but not the Magnus force (such as lift, due to spinning). Ask students if the flight paths when drag is included are parabolas, and if not, how they can tell (lack of symmetry). Ask students to sketch what they think the trajectory would look like with extreme backspin (temporarily curved upward). (page 3) Facilitate SCIENCE Inquiry Encourage inquiry using a strategy modeled on the research-based science writing heuristic. Student work will vary in complexity and depth depending on grade level, prior knowledge, and creativity. Use the prompts liberally to encourage thought and discussion. Student Copy Masters begin on page 11. Explore Understanding Give students a few balls to observe – including golf balls, ping pong balls, and superbounce balls – and ask them to compare and contrast them and their purpose. Students might think that golf ball dimples are simply a design feature with no other purpose. Use these or similar prompts to spark a discussion about the role of dimples in the design and manufacture of golf balls. The purpose of each ball is to.... Features of each ball that make it good for its intended purpose are.... Some characteristics golfers would want in an ideal golf ball are.... Because the dimples appear to be deliberate, their purpose(s) could be to.... Thinking of atmospheric conditions on the moon, the dimples would.... In order to see the effect of dimples, we must compare.... Show the video “Science of Golf: Evolution of the Golf Ball.” Continue the discussion of golf ball design and manufacture, with prompts such as the following: When I watched the video, I thought about.... According to the video, the advantages of dimpling golf balls were discovered when.... According to the video, the two purposes of dimples are.... The expert in the video used a “golf ball launcher” instead of a human golfer because.... Other important golf ball characteristics mentioned in the video are.... The properties of air that might influence a golf ball’s flight include.... The golf ball might behave differently on a course in Miami versus a course in Denver because..... Ask Beginning Questions Stimulate small-group discussion with the prompt: This video makes me think about these questions.... Then have groups list questions they have about the challenges that must be surmounted in order to create golf balls that maximize either distance or accuracy. Ask groups to choose one question and phrase it in such a way as to be researchable and/or testable. The following are some examples. What is the primary advantage of dimpling a golf ball? How do dimples reduce aerodynamic drag force? What force is created by the rotation of the ball as it travels through the air? What advantage does a force of lift provide? What disadvantages might forces due to the ball’s rotation create? How can we demonstrate a reduction in drag force due to dimpling? (page 4) Design Investigations Choose one of the following options based on your students’ knowledge, creativity, and ability level and your available materials. Actual materials needed would vary greatly based on these factors as well. Possible Materials Allow time for students to examine and manipulate the materials you have available, or allow them to brainstorm what materials they might need. Doing so often aids students in refining their questions or prompts new ones that should be recorded for future investigation. In this inquiry, students might use materials such as dimpled foam practice golf balls (readily available in sporting goods sections of stores), ping pong balls, and a slingshot (such as those found at http://www.marksman.com/slingshots.php). A fairly sensitive scale, such as a triple-beam balance or a digital electronic scale, may be needed. NOTE: The aerodynamic effects of dimples become apparent only at rather high relative air speeds (on the order of 50 miles per hour), so that many reasonable-sounding attempts to demonstrate the effect will have a null result (dimpled ball indistinguishable from smooth ball). Leaf blowers might create such wind speed, while hair dryers and most fans do not. Also, the Magnus force (responsible for the lift force discussed in the video) exists even for smooth balls and is only enhanced by the dimpling, so demonstrations of this—while interesting and informative— do not necessarily justify the use of dimples. For more information, see http://www.titleist.com/technology/details.asp?id=20 or http://www.grc.nasa.gov/WWW/k-12/airplane/dragsphere.html. Instead, students might investigate other variables such as material, size, and mass by constructing their own golf balls and comparing results. Safety Considerations To augment your own safety procedures, see NSTA’s Safety Portal at http://www.nsta.org/portals/safety.aspx. The Focused Inquiry described below uses a slingshot. While only ping pong balls and foam golf balls are being launched here, close faculty supervision is essential to ensure proper use, and to prevent students from launching more dangerous projectiles such as rocks or real golf balls. If leaf-blowers are used, students may need to wear ear plugs, protective headphones, or other safety devices to protect their hearing. Open Choice Approach (Copy Master page 11) Groups might come together to agree on one question for which they will explore an answer, or each group might explore something different. Students should brainstorm to form a plan they would have to follow in order to answer the question, which might include researching background information. Work with students to develop safe procedures that control variables and enable them to gather valid data. Encourage students with prompts such as the following: Information we need to understand before we can start our investigation is.... The variables in construction of a golf ball are.... The potential variable(s) we want to hold constant is (are).... To measure the effects of different golf ball designs on the path of the golf ball, we will.... To conduct the investigation safely, we will.... Focused Approach (Copy Master pages 12–13) Note to teachers: The two main hurdles to overcome in this inquiry are the need to control for mass and cross-sectional area, and the need for a great enough air speed to make the effect of the dimples apparent. The ping pong ball is nearly the same size as the practice golf ball, but has less than one third of the practice golf ball’s mass, so the mass of the ping pong ball needs to be equalized by adding mass (in the form of water or sand, perhaps) to the inside of the ping pong ball through a small hole. The initial experiment of dropping the balls will likely yield a null result, as the speed reached is too slow for turbulent flow to be induced by the dimples. The second part, in which students use a rather powerful slingshot to launch the balls, should provide enough speed to show the effect, assuming the golf balls are able to travel about 30 meters or more in the air. If the slingshot pouch is much smaller than the ball, it may be helpful to enlarge it, perhaps using duct tape. Students might also use a strong wind source such as a leaf blower to observe the effect. Finally, note that the practice ball must have dimples, NOT holes as in a WiffleÒ-style ball. The holes are likely to increase drag rather than decrease it, or at least behave much differently than dimples. (page 5) The following exemplifies how students could detect and measure the effects of reduced aerodynamic drag due to dimples, after controlling for cross-sectional area and mass. After students examine the materials you have available to detect or measure the effect of dimpling on aerodynamic drag force, ask them questions such as the following to help them envision their investigation. What aspects of the ball, other than dimpling might affect drag force? How do the size and mass of the ping pong ball and practice golf ball compare? How will we equalize the two balls if they are different? How will we know which ball, if either, had more drag force on it? What are some sources of error in measuring the size and mass of the balls? Students might first simultaneously drop two dense objects of very different mass, such as a medicine ball and a real golf ball, from the same height (of at least several feet). Then students might drop a real golf ball, a foam practice golf ball, and a ping pong ball from a height of at least several feet, simultaneously, in pairs. The pairs of objects strike the ground.... Drag forces seem to have great/little effect on pairs of objects because.... The variable changed in pairs of objects is ____, which causes.... Drag forces might be observable between some pairs and not others because.... Students might carefully increase the mass of the ping pong ball by adding some material, such as water or sand, to the inside of it until it has the same mass as the foam practice golf ball. The hole should be as small as practicable and may be carefully made with just about any sharp object. Ideally, it should be sealed with a minimal amount of tape or glue to keep the material inside and yet maintain a smooth exterior. Once more, students could drop the equal-mass balls from a height of several feet to see that they will strike at the same time. Encourage students to use video cameras or smart phones to capture the action for observation. Use prompts such as the following to guide students. The balls struck the ground at the same/different time(s) because.... We did/did not detect any difference in drag force due to the dimples because.... We believe the slight size difference (does/does not) matter, because.... A difference between this situation and a real golf ball struck by a club is.... Students might now take the practice golf balls, mass-equalized ping pong balls, and slingshots either outdoors (if it is not too windy), to a large gym (at least 30 meters long, with a high ceiling), or a long hallway (though a low ceiling can be difficult to work with). One student can be the shooter; another can watch the shooter to instruct him/her regarding keeping a consistent launch angle and pull-back distance; another can spot the landing point of the ball; and another might measure the distance travelled with a tape measure (or simple qualitative differences can be observed without formal measurement, using pieces of tape or flags to mark the landing spots). The two types of balls can be launched at an angle found by practice to yield the greatest distance (unless a low ceiling interferes), and any differences in distance travelled can be observed. If (as is recommended) multiple shots are made, the mass-equalized ping pong ball should be inspected to ensure it is not losing its contents. We will ensure consistent launch speed by.... We will ensure consistent launch angle by.... We will determine the distance travelled by.... Sources of error in this part of the investigation include.... To minimize the influence of these sources of error, we will.... To conduct the investigation safely, we will.... Students can then return to the classroom to discuss the results. We believe the dimples (increased/decreased/did not affect) drag force because.... A difference between firing the balls with the slingshot versus dropping them was.... Other factors that may make our results questionable include.... Some students might want to extend their investigation by shooting empty ping pong balls, ping pong balls with somewhat more mass than the practice golf ball, and perhaps WiffleÒ-style practice golf balls (with holes) to observe any differences and form hypotheses to explain such differences. Encourage students to write down their beginning questions even if time does not allow investigation. Media Research Option Groups might have questions that are best explored using print media and online resources. Students should brainstorm to form a list of key words and phrases they could use in Internet search engines that might result in resources that will help them answer the question. Review how to safely browse the Web, how to evaluate information on the Internet for accuracy, and how to correctly cite the information found. Suggest students make note of any interesting tangents they find in their research effort for future inquiry. Encourage students with prompts such as the following: Words and phrases associated with our question are.... The reliability of our sources was established by.... The science and math concepts that underpin a possible solution are.... Our research might feed into an engineering design solution such as.... To conduct the investigation safely, we will... (page 6) Make a Claim Backed by Evidence Students should analyze their data and then make one or more claims based on the evidence their data shows. Encourage students with this prompt: As evidenced by... we claim... because.... An example claim might be: As evidenced by the greater distance travelled by the dimpled ball, as compared with the smooth one when shot with the slingshot—and contrasted with the simultaneous landing when just dropped—we claim that dimples reduce drag force only if speed is sufficient, because turbulence “kicks in” only beyond a certain threshold speed. Compare Findings Encourage students to compare their ideas with others, such as classmates who investigated a similar (or different) question or system, or to compare their ideas with material they found on the Internet or in their textbooks, or heard from an expert they chose to interview. Remind students to credit their original sources in their comparisons. Elicit comparisons from students with prompts such as: My ideas are similar to (or different from) those of the experts in the video in that.... My ideas are similar to (or different from) those of my classmates in that.... My ideas are similar to (or different from) those that I found on the Internet in that.... Students might make comparisons like the following: My ideas are similar to those discussed by researchers, published on the Internet, who have done detailed studies of aerodynamic effects on dimpled versus smooth balls. I found that dimples cause laminar flow to break into turbulence at a lower speed, thus making a narrower “wake” behind the ball and less drag force. Reflect on Learning Students should reflect on their understanding, thinking about how their ideas have changed or what they know now that they didn’t know before. Encourage reflection, using prompts such as the following: The claim made by the expert in the video is.... I support or refute the expert’s claim because in my investigation.... I am surprised by our findings because.... My initial “common sense” thinking changed because.... When thinking about the expert’s claims, I am confused as to why.... Another investigation I would like to explore is.... Inquiry Assessment See the rubric included in the student Copy Masters on page 14. Incorporate Video into Your Lesson Plan Integrate Video in Instruction Visualize Concept Show the portions of the video from 1:42–1:56 and 3:33–3:48, pausing it to allow students to carefully inspect the air flow diagrams. Have students look closely for any difference between the position of the streamlines ahead of and behind the ball. Ask students to explain how this difference could explain lift. (page 7) Note to teachers Because a thorough explanation is beyond the scope of the video, the point to be made is that the air underneath the ball is deflected downward, and, via Newton’s Third Law, it exerts an equal and opposite (i.e., upward) force on the ball: the lift force shown. Homework Have students individually (or as part of small teams) research aerodynamic effects – such as the Magnus force – used in various other sports, like baseball (various pitches), tennis (top spin), and ping pong (many effects). A topic of discussion could be whether anything like dimpling is used for these balls. Using the 5E Approach? If you use a 5E approach to lesson plans, consider incorporating video in these Es: Explore: Use the Design Investigations section of the Facilitate Inquiry to support your lessons on the relationship among mass, force, and acceleration (that is, Newton’s Second Law). The main topic could be how the ball’s flight is altered by the forces acting on its mass to produce acceleration (any change in velocity, including slowing down or changing direction). Elaborate: Air flow around objects is an important field of study, with applications in many design and engineering problems. Have students do Internet searches on applications in which air flow must be considered. Excellent examples include aerodynamics of cars to maximize fuel efficiency and (perhaps obviously) how airplanes fly. Note that many web sites address the issue of lift on airplane wings, and some are more authoritative than others. Lift is a complex and multi-faceted issue, and opinions differ about how best to explain lift on airplane wings. Connect to ... Language Arts Although not used in the video, the word serendipity accurately describes the fortunate, accidental way in which dimpling of golf balls was found to be useful. The word is difficult to translate into other languages and its origins can take students on a foray into literature, history, and geography. Have students research the definition, history, and uses of the word. Conclude by asking students if the word applies well to the discovery of golf ball dimples, or if they can think of other, better examples—even in their own lives. Connect to ... Social Studies and Geography As the video shows, golf is a very old game. Have students research the origin of the game – something like it was played in China long before it appeared in Europe, for example – and where it spread, and why it might have become more popular in some places than others. Use Video as a Writing Prompt Explain to students that they will use the concepts from the video to explain what kind of standards golf balls are subject to, and what the point of establishing such standards is. Project the video segment discussing these concepts (3:57–4:54), showing it at least twice, or allow students to access the video on their own to replay as often as needed. Have the students write a paragraph identifying these standards, and explaining how the game would be different if there was not enforcement of or compliance with these standards. (page 8) COPY MASTER: Open Choice Inquiry Guide for Students Science of Golf: Evolution of the Golf Ball Use this guide to investigate a question about the design of golf balls. Write your lab report in your science notebook. Ask Beginning Questions The video makes me think about these questions.... Design Investigations Choose one question. How can you answer it? Brainstorm with your teammates. Write a procedure that controls variables and makes accurate measurements. Look up information as needed. Add safety precautions. Information we need to understand before we can start our investigation is.... The aspect of golf ball design we will be working on is.... The variables we will be working with are.... We will evaluate our design by.... To conduct the investigation safely, we will.... Record Data and Observations Record your observations. Organize your data in tables or graphs as appropriate. Make a Claim Backed by Evidence Analyze your data and then make one or more claims based on the evidence your data show. Make sure that the claim goes beyond summarizing the relationship between the variables My Evidence My Claim My Reason Compare Findings Review the video and then discuss your results with classmates who investigated the same or a similar question. Or do research on the Internet or talk with an expert. How do your findings compare? Be sure to give credit to others when you use their findings in your comparisons. My ideas are similar to (or different from) those of the experts in the video in that.... My ideas are similar to (or different from) those of my classmates in that.... My ideas are similar to (or different from) those that I found on the Internet in that.... Reflect on Learning Think about what you found out. How does it fit with what you already knew? How does it change what you thought you knew? The claim made by the expert in the video is.... I support or refute the expert’s claim because in my investigation.... When thinking about the expert’s claims, I am confused as to why.... Another investigation I would like to explore is.... (page 9) COPY MASTER: Focused Inquiry Guide for Students Science of Golf: Evolution of the Golf Ball Use this guide to investigate a question about the design of golf balls. Write your lab report in your science notebook. Ask Beginning Questions Why are dimples an important consideration in the design of golf balls? Design Investigations Brainstorm with your teammates about how to answer the question. Write a procedure that controls variables and allows you to gather valid data. Add safety precautions as needed. Use these prompts to help you design your investigation. The supposed effect of dimples that we will be considering is.... Other aspects or properties of the ball that might confuse our results are.... We will hold the size of the ball constant by.... We will hold the mass of the ball constant by.... We will detect or measure any differences in drag force on the ball by.... We predict that the dimpled ball will experience (more/less) drag than the smooth ball.... To conduct the investigation safely, I need to.... Record Data and Observations Organize your observations. This inquiry has multiple parts, as you methodically go about the process of controlling for variables such as size, mass, and speed. Results of Actions Taken Action Observation and measurements Comments Tentative conclusion Dropped two dense objects of very different mass Dropped three low-density balls of same size but different mass Dropped two balls of same mass and size, but one smooth and one dimpled Shot smooth and dimpled balls of same mass at same speed and angle (page 10) Ideas for Analyzing Data How did mass affect the fall of two dense objects of very different mass? Can you explain what you saw (perhaps in terms of something you have learned in a physical science class)? Did these results surprise you? How did mass affect the fall of three balls of approximately equal size? Should drag force have been the same on these three balls, or at least on two of them? Why might the same drag force affect these balls differently? How did a dimpled versus smooth surface affect the fall of two roughly equal size and equal mass balls? Is the result what you expected based on first viewing the video? How did a dimpled versus smooth surface affect the distance travelled for two roughly equal size and equal mass balls, shot with a slingshot? Is the result what you expected based on first viewing the video? If it is different from the results for the same balls being dropped, why would that be? What other variable seems to matter here? What sources of error might remain in this experiment, other than those for which we carefully controlled? How might you address these issues in a follow-up experiment? Make a Claim Backed by Evidence Analyze your data and then make one or more claims based on the evidence your data show. Make sure that the claim goes beyond summarizing the relationship between the variables. My Evidence My Claim My Reason Compare Findings Review the video and then discuss your results with classmates who did the investigation using the same or a similar system or with those who did the investigation using a different system. Or do research on the Internet or talk with an expert. How do your findings compare? Be sure to give credit to others when you use their findings in your comparisons. My ideas are similar to (or different from) those of the experts in the video in that.... My ideas are similar to (or different from) those of my classmates in that.... My ideas are similar to (or different from) those that I found on the Internet in that.... Reflect on Learning Think about what you found out. How does it fit with what you already knew? How does it change what you thought you knew? The claim made by the expert in the video is.... I support (or refute) the expert’s claim because in my investigation.... When thinking about the expert’s claims, I am confused as to why.... Another investigation I would like to explore is.... (page 11) COPY MASTER: Assessment Rubric for Inquiry Investigations Criteria 1 point 2 points 3 points Initial question Question had a yes/no answer, was off topic, or otherwise was not researchable or testable. Question was researchable or testable but too broad or not answerable by the chosen investigation. Question clearly stated, researchable or testable, and showed direct relationship to investigation. Investigation design The design of the investigation did not support a response to the initial question. While the design supported the initial question, the procedure used to collect data (e.g., number of trials, control of variables) was not sufficient. Variables were clearly identified and controlled as needed with steps and trials that resulted in data that could be used to answer the question. Variables Either the dependent or independent variable was not identified. While the dependent and independent variables were identified, no controls were present. Variables identified and controlled in a way that results in data that can be analyzed and compared. Safety procedures Basic laboratory safety procedures were followed, but practices specific to the activity were not identified. Some, but not all, of the safety equipment was used and only some safe practices needed for this investigation were followed. Appropriate safety equipment used and safe practices adhered to. Observations and data Observations were not made or recorded, and data are unreasonable in nature, not recorded, or do not reflect what actually took place during the investigation. Observations were made, but were not very detailed, or data appear invalid or were not recorded appropriately. Detailed observations were made and properly recorded and data are plausible and recorded appropriately. Claim No claim was made or the claim had no relationship to the evidence used to support it. Claim was marginally related to evidence from investigation. Claim was backed by investigative or research evidence. Findings comparison Comparison of findings was limited to a description of the initial question. Comparison of findings was not supported by the data collected. Comparison of findings included both methodology and data collected by at least one other entity. Reflection Student reflections were limited to a description of the procedure used. Student reflections were not related to the initial question. Student reflections described at least one impact on thinking. Lesson plans produced by the National Science Teachers Association. 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