I want to make friends..?

I'm going to a rodeo with my dad and his friends. One of his friends has 2 kids and they're around my age. There's a girl who's a year younger than me, and a guy who's just a couple months older than me. I kinda like this guy, because he's really cute and nice. I want to talk to them but I'm really shy. I hate going up to them and talking to them but they won't come up to me either. I really want to talk to them. I'm going to be there the whole weekend. Please help!!!