@punkdudette,
You can go about this one of two different ways.
Choice 1: Next time your crush is standing close to you, throw your arms around him and plant a kiss on his lips. If he doesn't push you away, but rather responds and kisses you back, then he probably likes you.
Choice 2: Just keep talking to him normally and let the relationship develop. If he is interested, he will find ways to let you know. Maybe he is a bit shy or afraid of rejection and is simply testing the water by showing a bit more interest in talking to you and standing closer. (After all, he may think your friend was trying to pull a fast one on him by telling him that you have interest.)
Choice 3: Ok, I know I said two choices, but there is a third choice. Why don't you simply ask him out? When he is standing close to you one day, simply look at him and ask if he would like to go see a movie together, or sit and have lunch together in the cafeteria (I get the idea that you are still in school, but if not, then forget the cafeteria idea.) Something along those lines. Nothing wrong with you asking him out and he might really like that.
Of the three choices, I would probably hope a girl would choose #1 with me, but that's because I like daring. My wife went with number 3 when we first met and she ended up getting me to marry her 34 years ago, so there is validity in going that route.
Choose wisely, young lady. lol And good luck.