Native English speaker for home classes

Hi!
I am looking for a native English speaker to give English lessons to two brothers (8 and 10 years old). Their English level is already very high, so the objective would be to improve their reading/writing and to engage in interesting conversations. Also, play with them and create a "native speaker" atmosphere at home. 
We are looking for a native speaker with experience with children, with energy and enthusiasm and who is willing to share experiences about his/her home country.
Schedule is Mondays and Tuesdays from 5 to 8.30 pm. We live in Avenida de los Andes (Campo de las Naciones area of town). Starting September 4th please.

Thanks a lot!