Researching a first snake

[makinguscrazie]

In our home we have many "pets". I know that it continues to be discussed if a snake can even be considered a pet or not. My eldest son who is turning 15 has been begging for a snake since he was 6. We have dogs, cats, parrots, a Iguana, a Bearded dragon but he continues to want a snake. The Iguana is his and he has continued to care and talk to others about her. We got her from the typical person that had her in a small aquarium and on a heat rock with no lighting.
Anyway he wants a snake. I originally did not want to buy him a snake as I couldn't stand the idea of feeding it. However now after two reptile shows and talking to breeders I am considering it somewhat.I don't want anything that is hard to keep (like the Iguana) and nothing that gets huge to eat the dogs:medteeths or cats. I can consider this because I talked to a few people who told me we can feed frozen instead of live food (as long as they will accept it). We have talked to a few people and seem to think that a corn snake may be the best idea and the least aggressive. I am thinking I should find someone in a show or a breeder locally so we can handle it. Can people add some advice on what type of snake they would suggest for a 15 year old RESPONSIBLE kid. Also please suggest what and how we look for one.
THANKS
From a mom that swore that she would never get a snake but have a kid that now wants to be a herpetologist so what is a girl supposed to do?