What does she mean by "get the finger"?
Answer from a Native speaker
By "get the finger", she's referring to the hand gesture with the middle finger raised. This is a rude gesture as it's the general nonverbal sign for "fuck off" or "fuck you". She's saying all the children would be "giving" her this hand sign if she wasn't strict. Ex: Excuse me! Did you just give me the finger?! Ex: After he was rude to me, I just gave him the finger and left. Ex: I get the finger from my friends all the time. It's a joke between us.