What do you think if I tell you I know a secret about my teacher and I'm going to snitch?
That sounds interesting. Why would you tell everyone about your teacher's secret?
My friend offered to pay me if I would reveal the secret to everyone.
I'm sure the money your friend offered you is attractive, but it's wrong to tell secrets about others. This could be very embarrassing for your teacher and they may be humiliated if the students or faculty find out. If the teacher is engaging in harmful behavior, you should then tell the school administrators about the behavior.
Nah I want to try and go viral on the internet.
I see that you have incentives to snitch, but are you sure it's worth it? You will see this teacher every day at school, so it's going to be super awkward. Also, as they say, snitches get stitches, so maybe some students might think you are untrustworthy?