Why are my knees making cracking sounds?

Question

hii =]

i am 15 years old. everytime when im sitting down on a chair, my knees would feel like they are being too stiff all the time when im sitting so then i would stretch out my legs and all of a sudden my knees would make this weird crack/pop sound. is there something wrong with my knees or is it just being stiff? :o happens with my jaws too. when i would not talk for awhile my jaws would feel stiff so i would move me jaws from side to side (i dont know if that makes sense but its like moving my jaws bak and forth horizontally = P ) hehe. so if anyone knows whats wrong please tell me ^^

sorry for my bad english :P

Answer 1

My knees crack when i squat too! it has benn doing that for about 6 years, i am 12!