To understand what makes a kite fly, you must first understand the importance of tow scientific principles- gravity and lift. Gravity is the force that pulls objects towards the earth. So, practically speaking, why is it the gravity does not pull down a kite that you are flying?
The answer lies in the second scientific phenomenon- lift. Lift is what happens when the wind pushes against an object, and lifts it up. Lift also depends on the surface area of an object. A greater surface area allow for more life .
When you run with your kite on a string, it is the wind that provides the lift that makes your kite fly. As long as the force of the wind is stronger than the force of gravity, your kite will keep on flying, but when the wind drops, your kite will surely come back to the earth.