Okay so I just went to a new school 5 months ago and there was this guy in my class,Ever since I met him I loved him! Then we started talking and flirting bad into the fourth week... We went skiing at school on day and I went down the hill first then he came straight into me and he fell on top of me.Then a couple days later we went out for a day then he dumped me... then we started flirting about 2 weeks later really badly,Until he transferted classes:( but after that it was fine he would always come up to me and lunch and use me as an arm rest or sit on my knee! Then we started going out again and we went out for a month and he dumped me right out of nowhere, but every night hed call me and say I love you so much,I haven't talked to him since last month when he asked me to go out with his best friend,and I kept saying NO! But now I'm going out with his best friend but I love him,what do I do how do I get him back?

Firstly he says he loves you. Then he asks you to go out with his best friend hmmmmm...
Ask him why does he keep breaking up with you. If he loves you and you love him then there is no reason for a breakup even though he wants you to be with his best friend and tell him this.
It does look bad going in circles but just think about how he feels. Maybe he's just confused. Talk to him and ask him why does he breakup with you, and tell him you're there for him because this sounds fishy if he says he loves you but he wants you to go out with his best friend. I think there's more to this story when you get his side of it. Update if you can.
It could also be that he doesn't think he's good enough for you since he's giving you away so try to have a serious chat with him on what's up.

If you find out he doesn't really love you then I guess his best friend does. And so that is why he gave you up.

If you're going out with his best friend that is probably the first thing you need to change before you get him back. Leave the friend because that's just mean to stay with someone you don't really like, especially when you like their best friend. Secondly I want you to consider that you should back off for a while. Guys don't like clingy needy girls (or at least guys that are the age I'm assuming you are talking about) you have to act like you don't care be flirty and friendly but not over the top... Like I said the first step is breaking up with the other guy.

Always remember that just because that guy might not want to be with you, even though you are head over heels for him, that just means that there is something out there that's above and beyond the expectaions that you have now.

I got to say hun, I don't know if its worth getting this one back. Don't get yourself caught in the love>dump>love>dump cycle. It's emotionally draining to not know where you stand. If you don't love the friend, break up with him (nicely). It won't do you any good in winning the boyfriend back, if that's what you are set on doing.