Voluntary Teaching for K-12 computer science classes in USA this summer

[Olga]

Dear all

I am a K-12 computer science teacher based in Athens and planning to
visit MIT from 11-14 Augoust to attend the scratch conference. I would
also like to extend my staying in USA and teach on voluntary basis in
computer science classes for K-12 grades for a week before 11 Augoust.
Places suitable are New York or Boston since conference I plan to
attend is in Boston.

Does anyone know something which can be of help?

Thank you in advance