What do you mean by "too friendly"? If it was flirting, it's probably nothing. People like to flirt, even if they're already in a relationship. If it was flirting and touching, that's a bit of a red flag, you might want to mention it to your friend. If they were touching and kissing, then you would definitely want to mention it to your friend.

You don't have to decide what to do for her. Just give her all the facts and let her decide what she wants to do with them.

make sure you saw what u think u did, then tell her

I agree With sweet_n_silly make sure your right then tell her x

confront him. or tell your friend. or do both...

When your friend is not around bring her boyfriend to a quiet place in the school yard (like a wall) and ask him if what you saw was true. Like I'll do an example.

"Hey what's up?" he askes
"I want to know if what I saw was true."
"What did you see?" says with a smile.
"You being nice to a girl that's not my best friend."
"Look, she was all over me."

You have to trust him and make sure you talk to the girl too. The girl wouldn't lie, trust me that happened to me. My boyfriend was flirting only, but make sure WITH the girl!

I agree with sweet_and_silly, and Cinders. Completely disagree with Buggie111! You do not have to trust the guy or the girl, every situation is different.

Any guy thats flirting with another girl is definatly not worth ur time. Just tell her, because she really needs to know. If u dont, and she finds out you have known this all along, that may just be an end to your friendship.

Just tell her what you saw and see what she says. If she is the jealous type she will probably flip, but then again she may not take it that seriously...I don't know her, but you do, so you will know how to approach her about it.

Let this time pass and then if you see it again I say that you should tell ur friend

yeah, make sure you know what you saw, and not jumping to conclusions. if your sure, tell her :)

Talk to the guy, and if you still suspect something tell your friend PRONTo before she gets hurt.

it depends, i agree with "heartmerlin2" talk to him, that girl u saw may b an old friend, a cousin maybe, if u still find it weird talk to ur friend(in a slow way) cause u dont want her to think u r acusing her boyfriend and if u r wrong,
u know what i mean, i hope it helps

Smack him down! Finish him! Tell your friend!