Student Challenge: Halving the Square

Waylon took the wrong measurements. To make his painting, he needs a square piece of paper 50 square inches in size, but he has one that is 100 square inches. How can Waylon make it the right size when he doesn't have a ruler or scissors?

For a blog point, place your answer in a closed envelope addressed to "Mr. Koch." Put your name and grade as the return address. Deliver it to Mr. Koch at school.

p.s. If you can't find me, your teacher can put it in my mailbox too!
p.p.s. You can add comments, but DON'T reveal your answer in the comments!