Good Dirt Bikes

What is a good dirt bike to jump / motocross?
My son is 10 and would like a dirt bike that can jump. Roght now has a XR80R (trail.) What is a good dirt bike to be fitted that will be able to jump.
Depending on your height, but average 10 years old would do well to something like a kx65. If he is too high then you could look at either the 2-stroke 85cc bike or a crf150r. However, only be sure to monitor it or take lessons in any of them is a big step from a xr80 and does not want to hurt him.
Robert/Kristen filming dirt bike scene