Do I really have to explain this? I feel like I must. But it might be awkward to hear. I found out my mom is dating someone I went to school with. She doesn't know I know.
Ooooh, no! You can't be seriously. You are fooling me, right? How do you feel about your mom dating someone you went to school with?
First of all it's really awkward, secondly he's a creep
I bet it is awkward having your mom date a creepy old acquaintance, she shouldn't be hiding the fact that she is dating him from you. She should be honest and open about her relationships, especially with her children.
I think she's a loser for dating someone that young.
Your mom is not being honest with you and that concerns me most. Have her talk about it with you and tell her what's on your mind about it. That could make her think twice about him.