Does it sound like my friend like me?

Okay, so, my friend and I have homeroom together... Which is Science cl. I'm always out of my 3rd hour early so I'm the first one there. I walk out of the room to talk to some friends of mine. I walk back into cl and I notice either my book is missing (yes, I am a book worm) or it's my pencil pouch. So I ask this kid Issac who took it. He always says my friends name. So, I walk up to him and say, "Can I have my stuff back?" He always replies "No Rebecca, you can't." I have to lliterallybeg him! I finally ask nicely and he finally give it back... He helps out the Science teacher, and when he goes and gets the stuff, he always walks up to me and hits me in the arm. He does the ssame thingin math cl too. Then, in math cl, I try to trip him because he walks right p me. But, when other people are around, he is mean to me. Then when we are alone and hanging out at the park by his house, he is really nice to me... I don't get it!! I don't understand why he's mean, then nice to me. My ma says its just because he likes me... but, I don't know.... Sorry if this is too long.