Overview
Straw rockets are a simple introduction to aerospace engineering and the physics of flight. You will roll paper into a nose cone and body tube, slip it over a straw, and launch it with a sharp breath. Then you will systematically change one variable at a time — nose cone angle, fin shape, body tube length — to see what makes a rocket fly farther and straighter.
What You'll Learn
- Newton's Third Law of Motion in a real application
- What center of mass and center of pressure are and how they affect stability
- How to control variables in an experiment (change one thing at a time)
- How fin shape and size affect flight path
Background
Rockets move using Newton's Third Law: for every action there is an equal and opposite reaction. Air pushed backward pushes the rocket forward. Stability determines whether the rocket flies straight or tumbles: a rocket is stable when its center of pressure is behind its center of mass. Fins at the tail move the center of pressure rearward, making the rocket fly nose-first.
Safety note: Launch away from people and animals. Point the straw downward before loading.
Materials
Everything on this list is either free or available at a dollar store. No lab equipment required.
Step-by-Step Procedure
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1
Build Rocket 1 (baseline)
Roll a half-sheet of paper tightly around a pencil to form a tube. Tape the seam. Slide out the pencil, pinch and tape one end shut, and shape the other end into a cone. Add two small rectangular fins at the tail.
💡Keep the tube tight and even for consistent results
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2
Launch and measure
Slide Rocket 1 onto a straw. Give a sharp short burst of breath. Measure where it lands. Launch 5 times and calculate the average distance.
💡Use the same breath pressure each time
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3
Modify Rocket 2
Change one variable: make the nose cone more pointed. Keep everything else identical. Test 5 times and calculate the average.
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4
Modify Rocket 3
Change another variable: make the fins larger. Test 5 times and record.
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5
Create a data table
Compare all three rocket designs. Which flew farthest? Which was most consistent?
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6
Build the optimized rocket
Using the best features from your testing, build a final optimized rocket and launch it.
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7
Document your findings
Write a brief conclusion: which design choice made the biggest impact on performance and why?
Expected Results
A well-built baseline straw rocket travels 10–20 feet on a standard breath. Optimization through nose cone and fin iteration can often double that distance. Unstable rockets visibly tumble. Stable rockets fly in a consistent straight arc.
Your results may differ — and that's valuable data, not a mistake. Document what you actually observed, not what you expected.
Going Further
Change launch angle
Hold the straw at 30°, 45°, and 60° angles and record which produces maximum distance.
Add nose weight
Tape a small paper clip to the nose cone and observe how it affects stability and distance.
