please help :)

My bf and I been dating for over two years now, & he's been friends with this girl since 4th grade ( now in high school ) well she rubs her legs against him at school and the other day I caught him smiling when she did it... and he said it's because it was awkward so he smiled. And every time I asks questions about her he would look away and answer or think about the answer he'll say. Do you think it's more than friends or just friends?