Brutally honest? They're a bit forgettable.
I'm sorry didn't specify enough, I mean what personalities do you see the character with based off their name!
Mary Gomez - Behind the scenes kind of teen, not many friends, kind of dislikes life.
Emma Knight - Bubbly out going blonde, with lots of friends. Is only really Mary's friend because they've known each other since Kindergarten. Tries to bring her out of her shell.
Derek Hershey - Light brown hair, hazel eyes. Handsome, but in a quiet way. Has his group of friends, but isn't exclusive to them. The guy that everyone knows on some level, but he's not the popular kind. Has some sort of quiet passion.
Mix up the syllables a bit. They're all 2-2. It's boring.
I agree with east93. With the addition of a football player for Derek.
Mary Gomez: Slightly Hispanic and quiet, with very dark eyes.
Emma Knight: Long hair, bubbly and perky, with a great sense of humour but slightly sarcastic
Derek Hershey: Sorry, but if you want brutal honesty, I think of the brand Hershey's chocolate. I think Derek Hershel (or Hershall? Hershell?) would be better.