Inside: This simple kite is super easy to make from an ordinary plastic bag! Make it during National Kite Month (April), for Ben Franklin’s birthday (January 17th), or any time of the year.
Every year we eagerly wait for the arrival of The Kite Festival that takes place every May on Cricket Hill in Chicago. We’ve bought a number of kites over the years to test at the festival, but nothing is ever as satisfying as flying our very own DIY kites.
There is something very enthralling about making and flying kites. In fact, if your kids refuse to put their devices down in order to go and play outside, don’t scold them. Instead, go ahead and make this kite and head outside to fly it together. I guarantee that at the end of many fun hours, you will return home pleasantly exhausted from laughter and all your kite-flying adventures.
The History of Kites
While the exact creator of the first kite will forever remain a mystery, we know for a fact that kites have been around for a very long time. Exactly how long ago wasn’t discovered until fairly recently.
At first, historians believed that the first kites were invented in China about 2,800 years ago. But that belief was put to rest recently when a cave painting of a kite was discovered in Indonesia dating back 9,500- 9,000 BC. That’s a much longer time ago! So what made them so important?
It sounds outlandish, but the first kites were not used for fun and games as they are today. They had important work to do. According to ancient sources, kites were used for testing wind, signaling, measuring distances, and communicating during military operations.
Kites were made of light wood and cloth, bamboo and paper, sticks and silks, and all kinds of other stuff, depending on the purpose and size of the kite.
No matter what kites were made of, however, they all had 3 main components:
- The kite body
- The bridle, and
- The control line
Let’s see how those 3 parts fit together to form a kite.
And by the way, if you want to turn this into a science lab, you can talk about what forces make kites fly, how the anatomy of a kite relates to its flying dynamics, and what variables affect the kite. Scroll down to the end for the science section.
How to Make a Simple Plastic Bag Kite
What you need
Grocery plastic bags
3 school pencils or kebab sticks
Tape or glue
Spool of light string (at least 30 feet)
Additional (some of it optional) equipment
Note: I’m going to use the glue gun in the steps below, but you can absolutely use sticky tape (like Gorilla tape) instead.
What to do
1. Put the pencils together
Connect 3 pencils in a cross shape with a glue gun.
As you can see in the pic above, I added a bit of support to the wings, so they wouldn’t tilt while drying.
Also, I later added a bit of tape to the eraser’s area to make it all extra secure.
2. Create a frame
Glue string to all 4 points of your cross to form a frame. I dab a bit of glue and quickly wind the string around both the pencil and the glue.
As you can see in the pic above, you start at one point and go all the way around till you connect back with the starting point.
3. Make a sail
Spread the cut-up plastic bag on the floor and place the pencil frame on top. We found from experience that lighter bags are actually better than more durable bags that are designed to be used more than once. Alternatively, you can use tissue paper.
We found this bright yellow bag in our junk bag drawer and were pretty excited about it.
4. Grab a marker
Use a marker to trace the diamond shape onto the plastic bag beneath. Leave a border for folding over.
If you have a steady hand, skip this step, and go straight to cutting.
5. Cut it out
Cut the diamond shape out of the plastic bag. Remember to keep a bit of border for gluing it over in the next step.
Glue the bag to the frame by adding glue to the border and folding it over. If you are using a glue gun, then hold the folded border down for a second with a stick or scissors to avoid burning your fingers.
If your bag is thin like ours, you might see some scorch marks from the glue gun. Nobody will notice them once the kite is up in the air 🙂
7. Make a kite tail
Just use whatever pieces of a bag you have left, or grab a second bag. You can also tie small pieces together to form a long tail.
If you want a colorful kite, use a pretty ribbon, but nothing too heavy, or it will make the kite harder to lift.
Here’s a secret: the tail helps the kite point into the wind. So be prepared to make adjustments on the fly 🙂 when you’re out in the field. Grab extra plastic bags and scissors as you head out the door because you might find out that you need a longer tail.
That’s exactly what happened to us. We had to add more and more pieces to our tail when we were already at the park to make it work better.
8. Create a kite bridle
We tried attaching the flying line directly to our frame to save time, but it didn’t work really well.
The bridle is an arrangement of strings that go between your kite and the flying line. It kind of looks like a harness and allows the string to move around, so your kite can adjust itself to catch the wind.
This step basically means that instead of tying the flying line to the frame, we first tie a string to the top of the kite. Then we tie two strings to the two sides. And finally, the last string goes to the middle point (where the pencils cross). Now, tie all 4 strings together, creating a harness.
Also, note that our harness is on the top side (not the underside). This way, when we’re flying a kite, we’re looking at the “best” side 🙂
The easiest way for me to attach the string was to thread the thread through the needle, push it through the plastic bag, and tie it. But you might come up with a different way that is easier for you.
9. Attach flying line
Tie a flying line to the bridle and head to the park! It helps a lot if it’s a very windy day!
Run in the direction of the wind! Release the flying line of the kite as you run. Obviously, the best way to enjoy kite flying is on a windy today (with winds at least 8-10 miles per hour).
Kites offer a great opportunity to learn about wind, the direction of wind, and wind power. Especially when your kite catches wind, you can really see this force of nature at work.
So go fly a kite! It sounds simple, but just looking up at the sky for a while (instead of electronic devices) will give you all a happiness boost (and we all can use more of that, right!)
The Science of Kites
No matter how lightweight the materials you use to make the kite, it’s heavier than air, and yet it needs to somehow ‘float’ on the air.
How does that work?
It all has to do with balancing forces. The first important force is, of course, Gravity, and the kite overcomes it with Lift.
Lift is an upward force buoying up the kite from underneath. It’s caused when the air moves over and under the kite. The air underneath is blocked by the kite, and you can imagine it building up, wanting to push through the kite, and forming a small mass of denser air.
This is why you want the kite to fly at an angle, not totally blocking the horizontal movement of air but creating a little obstacle that slows down the air and builds up the pressure on the underside. Because that dense air wants to push up to even out the air pressure again…voila, upwards force. Lift!
If it’s already windy, you’ll automatically get that air motion, but practiced kite flyers can make it work by running with their kite and manipulating those forces by hand. When a kite seems to sit perfectly still in the air, it means there’s also a balance between Thrust, the horizontal forward motion created by the tug of your string on the bridle and frame, and Drag, the friction between the kite and the air that wants to push it backwards.
When all four forces are in balance, you get a beautifully peaceful kite, surfing the air like a serene Buddha.