English classes in Mirasierra (Madrid)

We are looking for an English native teacher to teach our kids (6 and 8 years old): conversation, reading comprehension, grammar.. 
Two days per week, 1.30h each day in the afternoon (from 17.30h onwards) in Mirasierra (Madrid). 
We are looking for someone with experience in classes kids, to start as soon as possible and who wants to stay  at least the school year.
Thanks!