Curriculum & InstructionTeaching Elementary School Science

Using the Learning Cycle to Teach Projectile Motion

Learning Standards: Grade 3-4Iowa Science Standard (physical science) 3-PS2-2: Make observations and/or measurements of

an object’s motion to provide evidence that a pattern can be used to predict future motion.List Science Practices:

Developing and using models Planning and carrying out investigations Analyzing and interpreting data Obtaining, evaluating, and communicating information

List IC 21st Century Skills (employability): Communicate and work productively with others Demonstrate productivity and accountability by producing quality work Use interactive technologies in a collaborative group to produce digital presentations or

products in a curricular area

What students will be doing: In this learning cycle, students will be plan and carry out investigations on projectile motion with ping pong ball launchers to determine what affects the distance the ball will travel. Students will also learn about the aspects of motion such as angle, gravity, and force.

ENGAGE ______________________________Today we are starting a brand new unit in science. I’m not going to tell you exactly what the topic will be, but I will give you one hint: It has something to do with MOTION. There are lots of different kinds of motion. I’m going to show you a short video that will show you the kind of motion we will be studying - although we will not be trying this experiment here at school!This video clip is an excellent way to introduce projectile motion. Students may want to watch the video more than once. Go for it! Questions to ask students after the video include the following:

Do you think this is real or was it faked? Why or why not?How do you think they figured out where to put the pool?What if someone heavier went down the slide? Would they still hit the target? What if

someone lighter went down the slide?Did they really need that wooden ramp? Why or why not?At what spot along the route was the person going fastest?Why did the person go up then come back down? We are going to be studying projectile motion. Can anyone tell me what this video had to do

with projectile motion?

http://www.arborsci.com/cool/the-amazing-water-slide-human-projectile

EXPLORE ______________________________Materials: ping pong balls, launchers, measuring tape or meter sticks, masking tape, rubber

bands of various sizes/thicknesses. Launchers may be purchased through this web site: http://www.teachergeek.com/Projectile_Launchers-Ping_Pong_Ball_Launcher_Activity_10pk_2-html

Activity Set-up and Teaching Tips:Arrange materials in a fashion that makes distribution of materials and clean-up simple. Use box lids or lunch trays to help keep materials organized. Before class, set up enough sets to allow students to work in groups of 2-3 students. After the Engage video and subsequent discussion, students will be primed to further explore projectile motion. Show students the materials tray before distributing materials to the class. This will help maintain their focus during teacher directions. Simply show students the materials, including the word “launcher” for the name of the main device, perhaps asking students why they think this is called a “launcher”. Do not show them how to use the launcher - challenge them to figure this out on their own. It will become obvious they will be launching a ping pong ball. Be sure to include several rubber bands of various thicknesses on each tray and to tell students they will need to figure out how the rubber band is to be used, but that the launcher will not work without the rubber band. Resist the urge to tell kids how to attach the rubber band or work the launcher. Give them time to struggle and problem solve; they will be able to figure things out. Challenge students to mess around with the materials on their tray to try to discover three things: 1) how to work the launcher, 2) how to get the ping pong ball to go the farthest, and 3) how to make a ball go the highest. Tell students there will be no need to record data as they explore, but to be prepared to share their discoveries. Allow students 10 or 15 minutes to work with their launchers, depending on their level of interest and focus. Safety: Remind students they are not to aim the launchers at others; especially at heads. Also remind students it is their responsibility to retrieve their ping pong ball after launching it.

Introducing the Explore to Students:Gosh I love that video. Anyway, today you will have a chance to get a much better feel for projectile motion. Let me show you the materials. Each group will get a tray with your materials on it. We have a few rubber bands, a ping pong ball, a roll of tape, and a device called a launcher. Should we go over how it works? What fun would that be?

● Your first job is to figure out how to get the launcher to launch the ping pong ball. How will you know when it is working?

● Your second job is to figure out what you have to do to the launcher to get the ping pong ball to go the farthest.

● Your third job is to figure out how to make the ball go the highest. We will not be recording data for this exploration - but please remember what you did so we can talk about it. There is no need to do any measuring. Just eyeball what is happening. Here is one final note: Safety: No aiming the ping pong balls at classmates’ heads!

While students are exploring, move from group to group asking probing questions about what students have discovered. You may need to provide a hint or two about changing the angle of the device, but will find kids can figure it out with some skilled questioning.

Wrapping Up the ExplorationBring student groups back together and have them share their discoveries. Ask students questions such as the following:

● What did you do to get your ball to go far?● Did anyone notice how you were able to launch the ball with more force (pull the

trigger back farther or add a tighter rubber band)● How were you able to get the ball to go higher? (move the settings of the launcher so it

was at a bigger angle, or so it was pointing more toward the ceiling)● How were you able to get the ball to go farther? (Pull the trigger back farther and use

a “middle” angle that is not too high and not too low.)● Why do you think some students were able to get their ping pong balls to go farther? If

we pulled the trigger back all of the way shouldn’t the ping pong balls all go the exact same distance? How do you explain this difference? (the rubber bands on the launchers all seem to be different and some seem “better” than others because they are tighter.)

EXPLAIN ______________________________Introduce the critical terms by first asking students what new “words” do you believe are important in understanding this activity? Ideas will be strengthened if the class generates definitions where possible. Here are some of the important terms for this activity and samples of student generated definitions. Either create a word wall or anchor charts on which you build these definitions with student input: ●projectile motion: motion in an arc pattern of up, then down.●motion: any change in position from the resting position●force: amount of “push” given to an object●gravity: downward pull●angle: “steepness” as measured in degrees by a protractor●distance: how far from the launcher a ball travels as measured along the floor.●height: the tallest point a projectile travels before starting to fall.

Include a discussion designed to clarify main ideas and provide students with opportunities to think about the exploration activity in the context of the new terms. For example ask students Why do projectiles always come back down? (Initially a projectile’s speed is enough to overcome the downward pull of gravity. But as the speed slows, the projectile’s speed is no longer enough to overcome gravity and the object starts falling back to earth. It does not fall straight down because it still has some energy that is moving it horizontally due to its initial speed and direction.)

ELABORATE ___________________________Materials: ping pong balls, launchers, measuring tape or meter sticks, masking tape, challenge recording sheets (make copies for each student)

Introducing the Elaborate to Students:Now that you have some skills in working your launcher and you know some of the scientific terms related to projectile motion, it is time to be more scientific about collecting some real

data. In this part of the activity, you are expected to use measurements and record numbers. It will probably take a few days of hard work to collect enough data to answer each of the three challenges you are going to receive. Each challenge must be answered using what you know about a fair test. What are the important steps in setting up a fair test? (Writing a research question that has the independent and dependent variables mentioned in it, doing at least 3 trials, and trying to keep everything else constant.) I know you are anxious to get experimenting, so let’s take a look at the challenges. By the way, you can complete these challenges in any order you wish, but you need to try your hardest to record your data neatly and accurately and to answer every question on your data sheets. Distribute the challenge data sheets to students, one per student and walk students through each challenge and the other questions on each data sheet.

Challenge 1: Using the ping pong ball launchers, discover the exact angle needed to get the ping pong ball to go the farthest.

Challenge 2: How does pulling the trigger back differently affect the distance the ping pong ball travels?

Challenge 3: How can you change the rubber band to make the ping pong ball go the furthest?

Because we will be measuring this time, what are some good ways you might keep track of where the ball lands, then measure this distance? What unit will you measure distance in? Give groups a minute to talk about this, then share. In the first challenge you will need to measure the angle. This can be tricky. Either show students how to use a protractor for this, or there are good phone apps that measure angle. Students would enjoy using one of these. It is also critical you talk with the class about how to select logical angles to test. There data table has room for 4 different angles. Many times students will make poor choices about which angles to test. For example, it is not a good idea to test angles close to 90 degrees and close to zero because students already know those won’t go the farthest. They may also be tempted to test angles that are too close together, like 42, 43 and 44 degrees. Here is one way you might address this. One restriction you have that may cramp your style is that you can only test 4 different angles in challenge 1. We don’t have time to test every angle between 90 degrees (which is pointing straight up) and 0 degrees (which is pointing straight out). What are some ways you can decide which angles might be good ones to test? Remember, you want to find that one angle that makes your ball go the farthest. Students are likely to choose angles in between 0 and 90, which is good. Suggest they take measurements that are at least 5 degrees apart, but don’t tell them which angles to test. They can make these decisions as a group.

Check with each group to insure they are on task and to see how they adjust their launcher to test a variety of launcher angles. As you circulate from group to group, ask questions to get students to make their own plan about how the variables they are testing.

Bring student groups back together and have them explain their findings in terms of how the angle affects the distance a ping pong ball can be launched. Encourage students to use the new terms introduced during the Explanation phase.

Handouts for the Elaboration Phase:

Challenge 1 Data Sheet

Group Members: __________________________________________

Challenge 1: Using the ping pong ball launchers, discover the exact angle needed to get the ping pong ball to go the farthest.

What is your research question? _____________________________

________________________________________________________

Independent variable: ______________________________________

Dependent variable: ________________________________________

Name the variables you will hold constant: _______________________

________________________________________________________

Data Table: Launch Angle and Distance Ping Pong Ball TravelsLaunch Angle (degrees) Trials Distance Traveled (m)

trial 1trial 2trial 3Average

____________________________________________

trial 1trial 2trial 3Average

____________________________________________

trial 1trial 2trial 3Average

____________________________________________

trial 1trial 2trial 3Average

____________________________________________

Write a claim about what you discovered. ________________________

__________________________________________________________

Challenge 2 Data Sheet

Group Members: __________________________________________

Challenge 2: How does pulling the trigger back differently affect the distance the ping pong ball travels?

What is your research question? _____________________________

________________________________________________________

Independent variable: ______________________________________

Dependent variable: _______________________

Name the variables you will hold constant: _______________________

________________________________________________________

Data Table: Launch Force and Distance Ping Pong Ball TravelsLaunch Force (distance trigger pulled back)

Trials Distance Traveled (m)

trial 1trial 2trial 3Average

____________________________________________

trial 1trial 2trial 3Average

____________________________________________

trial 1trial 2trial 3Average

____________________________________________

Write a claim about what you discovered. ________________________

__________________________________________________________

Challenge 3 Data Sheet

Group Members: __________________________________________

Challenge 3: How can you change the rubber band to make the ping pong ball go the furthest?

What is your research question? _____________________________

________________________________________________________

Independent variable: ______________________________________

Dependent variable: _______________________

Name the variables you will hold constant: _______________________

________________________________________________________

Data Table: Rubber Band Force and Distance Ping Pong Ball TravelsLaunch Force _______________________

Trials Distance Traveled (m)

trial 1trial 2trial 3Average

____________________________________________

trial 1trial 2trial 3Average

____________________________________________

trial 1trial 2trial 3Average

____________________________________________

Write a claim about what you discovered. ________________________

__________________________________________________________

Sample Data Answers

Completed Data Table for Projectile Motion Elaborate Phase

Challenge 1

Challenge 2

Challenge 3

EVALUATE ___________________________Materials: PASCO soda straw launchers, access to computers with Flash. This will NOT work on iPads since they do not have Flash. Simulation website:http://phet.colorado.edu/sims/projectile-motion/projectile-motion_en.html or just google “phet”

Final Product:Students will collaborate to create a video to explain one component of projectile motion and will share this production with others. Students will be assigned a concept to illustrate and be given science terms that must be included in their presentation. In addition, their videos will use either computer simulations or the launchers themselves. Students reflect on the videos and make suggestions for improvement of future videos.Over the past few weeks you have really learned about projectile motion. Now it is time to see how well you can put all of the ideas and all of the new terms we have learned together. You are going to get a chance to make a movie BUT we don’t all want to make the same movie. Each group of students will receive our own assignment about what materials you will use in your movie and what question you will need to answer. Your goal is to teach what you know about projectile motion to whoever is watching your movie so they “get it.” And how do we learn science best? By doing experiments. So each movie will feature a different experiment. Each group will receive a sheet like this one. Show students one of the movie sheets. Notice how each sheet lists materials, location, question, and a list of science terms you must use in your video. There are also some tips about what you should talk about. Before real actors begin filming movie scenes, what do they need to do? (practice and memorize their script) That is what you will be doing as well. Each group must use this form (show the form) to write their script. Practice it when you have it written. Each person in your group must have a speaking part. Once you are ready, come get me to watch your practice. That is your ticket to getting the video camera. Let’s get started.

Teacher Tips: Require students to write a full script in which everyone has a speaking role. Once you have checked the script, then supply the camera for recording. It works best to provide each student group with a set of requirements for their video.

Additional Information for the Evaluation Phase: Including group assignments and student handout for video scripting

Student Group Assignments

Group Number

Students Filming Location

Main Materials Relationship Investigated Level of difficulty

1 Sam P & Sam S Hallway Ping pong ball launcher

Angle vs. distance Medium

2 Phynnex & Daniel Hallway Ping pong ball launcher

Force vs. distance Complex

3 Nika, Lexi & Molly Hallway Straw launcher Force vs. distance Medium

4 Aubreigh & Katie Hallway Straw launcher Angle vs. distance Medium

5 Bennett & Leighton Classroom Computer Initial speed vs. distance Simple

6 Alex & Cullan Classroom Computer Roller Coaster Simulation (Friction)

Simple

7 Aurion & Peyton Classroom Computer Angle vs. height Medium

8 Bianca & Gabi Classroom Computer Roller Coaster Simulation (steepness & loops)

Complex

The groups listed below stem from the table above, and provide specific information to each student group on their assessment tasks.

Group #1: Materials: Launcher, protractor, ping pong ballLocation: In the hallwayMain Question: What angle causes the ping pong ball to go the farthest?What you must show and talk about in your video:

Compare the distance a ball travels when shot at big angles (like 70 or 80 degrees), and a ball shot at small angles (like 10 or 20 degrees). What angle is best for distance? How did you discover this? Mention which variables you are keeping constant.Filming of this works best if you set up three separate launchers so their angles are all ready

and you can film quickly. Film 3 different angles.What words you must include in your video: projectile motion, distance, angle, force, variable,

and constant.Write a script of what you will say and who will say it:

Group #2 Materials: Launcher, ping pong ball, measuring tapeLocation: In the hallwayMain Question: How does the force you launch the ball with affect the distance it travels? What you must show and talk about in your video:

Explain the purpose of this launcherShow how you can change the force you give the ball. We did not study this in class, so

experiment with it first. Compare the distance a ball will go at different forces. Be sure to mention which variables you are keeping constant. What is your conclusion about force and distance? (What force is best for distance?)

What words you must include in your video: projectile motion, distance, angle, force, variables, and constant.Write a script of what you will say and who will say it:

Group #3:

Materials: Soda Straw Launcher, straws, clay and scissorsLocation: In the hallwayMain Question: How does the length of the straw affect how far the soda straw travels?What you must show and talk about in your video:

Compare the distance a soda straw travels as it is shortened. Explain which variables you will leave the same (initial force, amount of clay, angle) and which

variables you will change (length of straw). What words you must include in your video: projectile motion, distance, launcher, force, angle, variables, and constant.Write a script of what you will say and who will say it:

Group #4 Materials: Soda Straw Launcher, straws, clay and scissorsLocation: In the hallway

Main Question: How does the angle affect how far the soda straw travels?

What you must show and talk about in your video: Compare the distance a soda straw travels as the angle changes. Explain which variables you will leave the same (initial force, clay and straw) and which

variables you will change (angle). You will probably only have time to film 3 different angles. Pick a big one, the best one and a

small one. What words you must include in your video: projectile motion, distance, launcher, force, angle, variables, and constant.What words you must include in your video: motion, speed, angle, gravity, friction.Write a script of what you will say and who will say it:

Group #5: Materials: computer with projectile motion simulationLocation: In the classroomMain Question: How does the initial speed affect how far a launched ball will travel? What you must show and talk about in your video:

Compare the distance a ball goes when its starting speed is changed. (Start at a small speed and gradually increase the initial speed)

What initial speed is best for going the greatest distance? How did you discover this? Be sure to mention which variables you will keep constant in your trials.

What words you must include in your video: projectile motion, distance, angle, initial speed, variables and constant.Write a script of what you will say and who will say it:

Group #6: Materials: Computer and projectile motion simulationLocation: In the classroomMain Question: How does the angle a ball is shot affect the distance the ball travels? What you must show and talk about in your video:

Compare the distance a ball goes when shot at big angles versus small angles.What angle makes the ball go the farthest? How did you discover this?

Be sure to mention which variables you will keep constant in your experiment.Words you must include in your video: simulation, projectile motion, height, distance, angle, variables, and constant.Write a script of what you will say and who will say it:

Group #7: Materials: Computer and projectile motion simulationLocation: In the classroom

Main Question: How does the shooting angle affect how high a ball will go?What you must show and talk about in your video:

Compare the height a ball goes when shot at different angles.Explain which variables you will leave the same (initial speed, mass, type of object) and what

you will change. What words you must include in your video: projectile motion, height, initial speed, and angle,

variables, constant.Write a script of what you will say and who will say it:

Student Record Sheet:

Names: _________________________________________

Projectile Motion Video ScriptIntroduce yourself: ______________________________________________________________

_______________________________________________________________________________

_______________________________________________________________________________

State your Question: ______________________________________________________________

_______________________________________________________________________________

_______________________________________________________________________________

Show your Materials: _____________________________________________________________

_______________________________________________________________________________

_______________________________________________________________________________

_______________________________________________________________________________

Demonstrate the Experiment:

Say which variables you will keep constant: _____________________________________

__________________________________________________________________________

__________________________________________________________________________

Say which variables you will change: ____________________________________________

___________________________________________________________________________

___________________________________________________________________________

___________________________________________________________________________

State your Conclusion: ______________________________________________________________

_________________________________________________________________________________

_________________________________________________________________________________

_________________________________________________________________________________

_________________________________________________________________________________

Rubric for Scoring Student Script and Presentation:

Focus area 1 2 3 4 Score Total

Mechanics/ Grammar of Written Script

Script has four or more spelling and/or grammatical errors or errors in sentence structure.

Script has three misspellings and/or grammatical errors or errors in sentence structure.

Script has no more than two misspellings and/or grammatical errors or errors in sentence structure.

Script has no misspellings and/or grammatical errors. Sentence structure is correct.

Knowledge of Subject

Presenters do not have a grasp of the content; questions about project cannot be answered. Required terms are not included and/or are not used properly.

Presenter seems to be uncomfortable with information and is only able to answer basic questions. Two of the required science terms are either not included or are misused.

Presenter knows information about activity but is hesitant to elaborate on answers to questions. One of the required science terms is either not included or is poorly used.

Presenter demonstrates full knowledge of activity results and is able to elaborate on answers to questions. Required terms are all used properly within the presentation.

Organization of Presentation

Audience has a difficult time understanding the presentation due

Audience has a difficult time following along since the

Audience can follow along since Information is presented in a

Audience is engaged in presentation; information is interesting and follows

to lack of sequence

presenter jumps from one topic to another

logical sequence a logical sequence

Eye Contact Presenter reads entire script and makes no eye contact with audience

Presenters reads most of script and only occasionally makes eye contact

Presenter makes eye contact most of the time and only uses script frequently

Presenter seldom uses the script during presentation and maintains eye contact throughout

Elocution Presenter mumbles and speaks too quietly for most students to hear

Presenter’s voice volume is low; some students have a difficult time hearing presentation

Presenter’s voice is clear and most students are able to hear the presentation

Presenter uses a clear, loud voice and all students are able to hear the entire presentation