English or Bilingual Schools? (Buenos Aires)

Hi there,
My family will be moving to Buenos Aires next year and while my husband and I have a little Spanish, our children do not. I want my sons (they will be 8, 6, and 5) to learn the language but do not want to throw them into a completely Spanish-speaking school right away where they would be overwhelmed and perhaps suffer academically. If anyone has any suggestion for schools I should look into I would be grateful! By the way, with 3 tuitions to pay, a reasonable cost is a plus.
Thanks!