How To TellThere are many different ways. If a boy acts like one of these or more, he might like you.
1. He's rude to you
Now, I know this may sound really weird, but if a guy is really rude to JUST YOU (If he's also rude to other people he may be just a rude person.) then he probably likes you. Boys don't always know how to show their feelings to girls so he may be trying to get your attention.
2. He tells you jokes
A kind of flirting is humor. If he tells you jokes and seems pleased when you laugh, he likes you! Laugh along to his jokes.
3. If he brags a lot
Again, this may be annoying like #1, but if he's bragging he may be trying to show off and impress you. (Or he's just a braggart)
4. If he talks to you
If he asks you lots of questions and talks to you, he might like you. Every chance he gets he'll try to come be with you, so that may be a sign of a crush.
5. If he makes any physical contact with you
Even if it's a small brush with his hand, if he's doing it on purpose he may like you. Or he just bumped into you in the crowded hallway. :)