Water Rocket Engineering Project - Lesson Cookbook p1
Water Rocket Engineering Project
Lesson Cookbook
Dan Miley
Steve Cogger
Andover Public Schools
Middle School Engineering
June 2009 R1.2
Over the past few years we have made thousands of rocket launches at our schools. We have guided our students through the engineering process as they design, build, and optimize their creations. And yes, we even launch in the winter!
The water rocket project is well known and has been done by many others before us. The following is merely our attempt to share the knowledge and experience we have accumulated to make things easier. Having 24 enthusiastic 6th graders using razor knives and hot glue guns can be harrowing enough! Our intent is to provide you a starting point to aid in your implementation of the project. Engineering is a process of designing and improving an idea, this project is no different. We welcome your ideas, and comments so we can improve our design.
Preparation
As much fun as "winging it" can be in a classroom, it can get a bit dicey with this project. Running out of materials can really ruin your day! Prior to your class, it really helps if you have about 1.5 times the number of kids worth of materials cut and ready to go. Having pre-cut foamcore for fins and oak tag for nose cones and fin templates, really helps things go smoothly.
Safety
This project can be dangerous. The rockets take off at 50-60 MPH and land at 25-30. A "crash lander" rocket will embed itself in a moist field like a lawn dart. Do not let a student put ANYTHING in or on the rocket that you have not approved. Be on the look out for things like toy soldiers, golf balls, spikes, or anything that could become an unintended projectile. Be aware of the wind and position kids in places so they can run away from a stray rocket.
Inside, the safety issues are more obvious. As we tell the kids, "hot glue guns are hot". Don't be surprised if one or more decides to challenge your warning and instead constructs his or her own learning. Generally this is accompanied by a squeal of pain as they realize that it is hot and yes it sticks like glue so until it cools off it's going to burn. Low temp glue guns can cause first or second degree burns so a trip to the nurse is probably a good idea once the glue is peeled off.
Razor knives can definitely ruin a kid's day. A slip in the wrong direction will require a trip to the Emergency Room. Don't be afraid to say this to your class! Let them know that any sign of blood means a visit to the nurse.
We do not require the kids to make their cuts or anything else that makes them uncomfortable. It is important to let them know that their grade will not be affected if they ask you to cut the fins. Make sure that they understand that if they do choose to cut that they will agree to follow the rules and your instruction. If they don't, they take a seat. You can not tolerate any horseplay with knives.
To help control the cutting, chose one spot in the classroom and allow only 4 kids at a time to cut. When one student finishes cutting, call up another one. We'll talk about what kids do while they are waiting later. Use cutting tees to help avoid accidents from slipping knives. Don't be afraid to step in if a kid is really struggling with a knife. As simple as it looks, kids do have trouble cutting foam core. If their cuts are “chunking,” it’s likely a dull blade, too much cutting pressure, or both.
Each student needs to bring in a bottle for the project. Start asking them to bring in bottles about 2 weeks before they will need them. Make sure they are clear that it has to be a bottle that held fizzy stuff. Bottles that held still water may not withstand the pressure of the launch. You may hear that "we don't drink Coke in our house". Since we don't care what was in the bottle, as long as it was fizzy, tell them to buy the cheap stuff and pour it down the sink. The bottle must have a standard neck and cap size to fit on the launcher. Either one or two liter soda bottles both make good rockets. You can ask students what the tradeoffs are for either choice.
Lesson Outline
We will present a couple of lesson plans to help you decide what implementation will work in your curriculum. The maximum plan represents about 19 45-minute class periods. The minimum plan can be accomplished in 6 or 7. The notes and suggestions may give you additional ideas to adapt the timing as required.
Full 18 Day project
Day 1: Paper Airplanes- One day project to introduce and practice
the concepts of defining measurable
objectives, testing with measurements and
observations, and design improvements. / Can be skipped
Day 2: Project Introduction and Theory
- Forces and motion, Newton's Laws
- Aerodynamics, Lift, Drag, Thrust
- Safety expectations
- Project Schedule / If you have covered forces other sections of the curriculum this can be shortened.
Additional content for this day can include showing the project as it is done at MIT and the story of PET bottles.
Day 3: Project Outline
- Grading Sheet
- Rocket Considerations sheet
- Class discussion of possible objectives
- We show them ranges of performance
parameters to help them set their
measurable objective
- Design Brief
- Start Design Brief as time permits / We use the Rocket Considerations as the Research step in the design process.
It is worth the time to explain all parts of the design brief and the decisions they will make in each step.
Day 4: Complete Design Brief
- Students will complete their design brief.
- When complete have them do a peer review
of the Design Brief
- Peer review includes checking objectives for
proper range and units
-Make Fin Templates / Kids can't wait to get to the knives! We start the class by saying no knives today, only fin templates. Since they know they will not cut, it slows them down and helps them focus on design.
Day 5: Start Building the Rocket
- SAFETY discussion on knives and glue
guns again!
- 4 kids cut fins
- While waiting to cut kids sand and mark fin
alignment lines on bottles / Most kids will be able to cut their fins today. If they move along some may start gluing the fins on the bottle. How fast this moves is really a function of the class dynamic and how many kids try to make spinner rockets.
Day 6: Glue on Fins and Make Nose Cones
- Good time to review Lift and Drag and how
they relate to the fins and nose cone.
- Review Center of Gravity and Center of
Pressure and why clay aids stability.
- Glue on fins
- About halfway through you can show how to
make the nose cones. / Have the kids partner up to glue on the fins.
CAUTION! Remember that the top of the bottle is the bottom of the rocket. If the kids forget the fins go on the wrong way. You can show this to the class. Ask the partner to check fin direction as the builder starts to glue.
Day 7: Recovery Systems
- Tennis balls, crash landers, parachutes
- Make sure that they glue in the clay. It
shrinks overnight and will fall out. / Today can be a challenge! Some kids will be done quickly as they just have to glue in the clay and tape on the nose cone.
Others will need time to build parachutes and perfect their cone holding system. Kids are generally good especially if you can direct the kids who finish early to help if asked. Many will decorate their fins and nose cones.
Day 8: Form Launch Teams
- First Flight Data Sheet
- Review launching safety
- Explain inclinometer use
- Form launch teams / Reemphasize the speed on launching and landing. No chasing falling rockets!
How deep you go on the trig theory of the inclinometer is up to you
When forming teams there is one rule: Don't say No if asked to be on a team. Some kids get hung up if they don't know enough kids in the class or don't see enough kids at their table.
Day 9 & 10: Launch Day!
- Plan on 12-13 launches per 45 minute class
Note: It’s possible to launch 25 rockets in one class but requires a lot of organization! / Day 1 of the launch takes more time as the kids need to figure out what is going on.
NOTE: Launch at 60-65 psi. It helps keep the fins on, especially in the winter
Day 11: Redesign
- Post Flight Analysis and Redesign Plan
- Analyze the data
- Redesign the rocket to try to meet or exceed
the objectives / Tomorrow is repair day so set the expectation early that today is just redesign and analysis.
If things didn't work kids may try to turn a parachute into a crash lander. Encourage them strongly to try to fix what they have, and not to quit.
Day 12: Repair
- Fix rockets and make changes
- Second Flight Data Sheet
- Form new launch teams / Repairs should be limited. Don't let them rip off fins and start over. Bashed nose cones can be fixed with a recovery cone.
Save the clay if possible so it can be glued into a new nose cone
Day 13 & 14 Second Launch / As with the prior launch
Day 15 & 16 : Final Report*
- Final Report
- Review report page by page
- Collect all prior sheets, Design Brief, Flight
Data Sheets, Redesign Plan
- Work on report
* Alternative - Assign and explain in class and
have them do this for homework. / We allocate 2 days of class time for work on the final report and collect it a week after the first day. If they stay focused most will complete the Final Report in class.
You can save the graphing on page 3 until the second day.
Day 17, 18, 19: October Sky *
- Show October Sky
- Splits pretty well over 3 periods with pre and
post discussion
* Alternative - Show Mythbusters “Bottle
Rocket Blastoff” episode (26 mins). / Fun movie to show at the end
Also fills in on days when you have to cancel a launch due to weather.
Caution: It is rated PG mainly for language. There's a few SOBs, S**ts, and Bastards. You decide how to handle it!
Assessment
The great thing about this project is that the kids decide what they want to do. They pick their objectives and attempt to meet them. They may totally fail and not meet any objective. They have to know that this is OK. Make it clear that they will never be graded on how well their rocket flies. They will be graded on how well they carry out the design, building, flight and post-flight analysis/observation, and in how well they work with the teacher and with each other.
In Engineering we are teaching about a process with uncertain outcomes. All that matters is: What did the try to do? Did it do what they wanted? If not, why not? If yes why did it? How will they improve what they did? Kids are so used to the single right answer that they may have trouble dealing with the idea that failing is OK.
The Short-Cycle Alternative Schedule
Rick Rogers, a 6th grade Science teacher in Lexington, MA, uses the materials he got from Dan Miley to do the rocket unit at the end of the year. He says that this is the perfect way to end the year and that his kids love doing it. He does some things differently that allows the project to be done in less time. Note that Rick has two 50 minute and two 60 minute classes per week rather than the four 45 minute periods in Andover.
1) Students work in teams of 3 rather than individually. Fewer rockets take less time.
All launches can easily be done in less than one class period.
2) Post-flight assessment and modifications or repairs are done in a single class.
3) The final report may be skipped if they run out of time at the end of the year.
Day 1: Introduction*- Forces of Flight
- Paper plane design & test (short)
- Pick groups of 3, two if needed
- Hand out and introduce design brief / Draw a plane on the board and discuss 4 forces of flight. Talk about pitch, roll, and yaw of paper planes.
Day 2: Complete Design, Start Building
- Finish and peer review Design Brief
- Start the building process / Students can work in parallel to do the design brief. Teacher or peer reviewer signs design off to allow team to build.
Days 3-4: Complete building
- Finish rocket
- Define roles for launch team
- Review how to collect data
- Hand out first flight data sheets / Students work as a team to build the rocket. Team and rocket must be ready to fly at end of 4th class.
Day 5: First Launch / Shouldn’t take the whole period. Can come in to finalize notes.
Day 6: Assessment and Rebuilding / Concentrate on most important changes or repairs. Must be ready to fly at end of class.
Day 7: Second Launches
- Complete launches
- Hand out Final Report
Day 8: Final Report / Should be able to complete in class