There are two ways to go here:
You go and check with the girl to see if they really do like you
or
You ignore it and treat it as an April Fool's joke
You could but that would hurt their feelings when you say "APRIL FOOLS DAY!!!!!"
You go up to her. If her friends are around, make them leave. Then you ask her if you want to go out. Wait for her reaction. Then say April Fools. Note: get out of punching and/or slapping distance.
Sometimes if it is something that he really likes and you do a trick on him about it it's not so good.
Move on
When a woman sees a man she likes, she smiles.
You like each other.
He's playing you both for fools, if he cheats on you with her, he'll cheat on you with someone else. Move on.
Tell them that a certain girl in your class likes them, and then give an obvious hint. Use different names.
Life is a game of chance, there are two ways this can result: A happy relationship, or a humorous reject. The best thing I did was ask out a girl on April fools dsy so that if she said no I would say April fools. Try to get yourself in the most assuring position then ask him out. Like most other people say there always more fish in the vast ocean.
Just start talking to him the same way you talk to your friends or family.
Nothing happens. He will like you and since you don't like him ignore him. He will out grow it or find someone else to like. I promise you that in 5th grade he will like someone else.
Nothing! That someone if wants to share his feelings about the one he/she likes, would surely tell you something about him or her, but if that someone wants to maintain the privacy level, he/she will not reveal anything to you. Simple!