Jean: We’ve got to help him!
Scott: You’re reading my mind again?
Todd: Come back to… finish me off…?
Jean: Can’t… do it…
Todd: Thanks for… trying guys, but… it’s really not… worth it…
Todd (thinking): Why couldn’t you have just left me there?
Jean: Scott he’s —
Scott: —a mutant? Yeah, no kidding.
We have to get back to Professor Xavier and ask him how he wants to handle this. Hopefully Todd can join us at the institute.
Jean: I don’t think he will. I read his thoughts, just for a second and—
Nothing. Never mind. I guess we all feel that way at the beginning.
(X-Men: Evolution #3)
Basically Toad was getting bullied and tried to kill himself and his English class by crashing a bus.
Also Jean was probably feeling suicidal recently as well based on her last statement.