🪁 Does a longer tail keep a kite steadier?

My hypothesis

If I change how long the kite's tail is, then how many times the kite spins or dives in 30 seconds will ______, because ______.

🔊 You fill in the blanks. Think about which way the tail pulls when the kite starts to twist. A guess is a good because: the test finds out.

Change, measure, keep the same

Scientists call the thing you change the independent variable and the thing you measure the dependent variable. The things you keep the same are the controls: if one of them changed too, you wouldn't know which change made the difference. Try each of the 4 levels 3 times.

What you need

• 📄 Paper: 1 sheet
• 🥤 Straws: 2
• 🧵 String or yarn: about 6 m
• 🛍️ Plastic bags: 1, cut into strips for tails
• 📏 A tape measure, or a long ruler
• ⏱️ A stopwatch or a kitchen timer
• ✂️ Kid scissors
• 🩹 Tape

Steps

1. Lay a sheet of paper tall, and tape a straw down it 4 cm in from each long edge.🔊
2. Tape the ends of a 60 cm string to the two side edges, a third of the way down.🔊
3. Tie your long flying string to the middle of that short string.🔊
4. Cut strips from a plastic bag and tape them end to end into tails 50, 100 and 150 cm long.🔊
5. Go to an open field, far from power lines, trees and roads, and let out 5 m of string.🔊
6. Fly it with no tail, walking steadily into the breeze for 30 seconds.🔊
7. A helper times it and counts every spin or dive at the ground, and you write it down.🔊
8. Fly it two more times with no tail.🔊
9. Tape on the 50 cm tail and fly it three times, then the 100 cm and 150 cm tails.🔊
10. Find the mean for each tail and draw a line graph.🔊

Every step is one you can do yourself, with a grown-up nearby. Write each number down straight away, in the table below, so nothing is lost.

Your results table

From 4th grade, add the tries for each level and divide by how many there were: that's the mean, and it goes in the last column. Then draw a line graph, because the thing you change is a number that goes up.

Why it works

🔊 A kite twists when the wind pushes harder on one side than the other. A tail drags behind in the wind and pulls the bottom of the kite back into line, like the flights on a dart. A very long tail also adds weight and makes the kite droop, so there is often a best length in the middle.

Going further (7th and up): Change a second thing: make every tail from paper strips and from plastic strips, and draw a line for each.

Board layout

This project at your grade

From 4th grade up, the table gets a mean column. See every project for 3rd grade, or print a blank results table.

What a judge will ask

• What did you change, and what did you measure? I changed how long the kite's tail is and measured how many times the kite spins or dives in 30 seconds, in spins and dives.
• What did you keep the same, and why does that matter? I kept the same kite and the same 5 m of flying string the same, so the only difference was how long the kite's tail is.
• How many times did you test it? 3 times at each of my 4 levels.
• If you did it again, what would you change or test next? I'd make every tail from paper strips and from plastic strips, and draw a line for each.

Make it yours

Keep this project on this device and Peabody counts down to your fair day, with a plan for each day. Nothing is sent anywhere.

Try next

• ✈️ Which wing shape flies farthest?3rd–8th grade · 1 day of testing · free🚗 How things move · ✂️ Paper, tape and toys
• 🪂 Does a bigger parachute fall slower?3rd–8th grade · 1 day of testing · free🚗 How things move · ✂️ Paper, tape and toys