Could you please help me check these few sentences? Thank you.

1) I'm happy our head science teacher is so enthusiastic to carry out a project with your and the French school.
2) I read you both agreed to hold the meeting on 27 January and that you are going to provide for a hotel accommodation yourselves.
3) Let me know if you need any help from our side.

1) I'm happy our head science teacher is enthusiastic about carrying out a project with your and the French school.

Just about every time you use "so" or "such" in a sentence, there needs to be a "that..." clause following it (not as a separate sentence, though). Example: He was so enthusiastic that the others were feeling the excitement, too.

2) I read that you both agreed to hold the meeting on 27 January and that you are going to provide your own hotel accommodations.

3) OK