What should i do?

So i have this guy friend and we have gotten pretty close this year. In one of our classes he sits right in front of me and all this week he has been turning around every 5 seconds to look at me and then just smiles and turns back around. Every time, it makes me laugh and i jokingly say ‘can i help you?’ or ‘what’s your problem?’ And every time he just laughs and turns back around and does the same thing again. He also says things that are really funny but only to me. To other people he is just normal and does his work. This morning one of my friends said that she liked the same guy. At this point i didn’t know what to do because i was starting to like him too. So i just said yeah you guys would be really cute together. Anyways today he kept getting out of his seat and going to the back of the room where i was to look for something in his backpack (which was right behind me because this teacher made us put out backpacks in the back of the room) and he did this like 3 times in the span of 45 minutes. Every time, he would talk to me about things that we both liked and every time, he would go back to his seat because he couldn’t find what he was looking for. When he got to his seat, he would keep doing that thing where he turned around to look at me. So now i don’t know what to do because my friend likes him and so do i. What should i do?