A: How's your new math teacher?

B: He is a nice and funny teacher.
A: Really? That's great.
B: Yes, I like him.
A: Does he give you homework?
B: Yes, he gives a lot of homework to us, so I have no time to play.
A: That's too bad.

(Would you check the dialogue, pleasse? Thank you? Are the expressions all grammatical?)

Yes, they are grammatical.

Sra

Yes, the expressions in the dialogue are grammatically correct. The conversation flows naturally, and the expressions used by both individuals are appropriate in the given context. Well done!