Do you think he likes me? What should I di? HELP!?

So I've known this guy since 3rd grade. We've been in the same class since 3rd grade too. i know in 5th grade he used to like me, but in junior high we kinda stopped talking. We used to text, but he switched phones and never asked for my number. He's kinda shy. He laughs a lot around me and is funny and stuff... but he acts that way a lot around a bunch of different girls. His parents are getting divorced and i think I'm the only girl who knows. (He didn't tell me. My mom's friend is dating his dad) Thursday is our last day of school and he's teling one of my friends who he likes. I really like him, and some people thought we wiuld make a good couple. But in Science class, he always sits by my friend Sabrina, and no where near me... So do you thin I wshould tell him on the last day of school? Or flirt really heavily with him, and hope it goes somewhere. SOmeone give me some advice please.