2010-2015 (not 100% positive) about teens with superpowers that join a group

[Truman]

I do not rem. much about the book, but all I do rem. is that the main character either has ice or electric type powers and that the kids need to stand on some special platform in order to make their powers appear. I remember a certain dialogue where the main character is trying to picture some type of molecules forming and getting denser until he makes some sort of small cloud. I do not know the name of the characters but I think the three main characters where 2 boys and a girl. I'm pretty sure that it might be a scholastic book because I think i got it from the book fair back in elementary school.( I know I'm pretty young). I do know for sure that it's not michael vey.