Originally Posted by Ellipses
What is the difference in compacting, differentiation, and old-fashioned (evil) ability grouping? I have not seen differentiation work, but how did teachers ability group back in the day.

Ability grouping is not evil -- I assume you were being sarcastic. In the absence of ability grouping by classroom, affluent parents effect some degree of ability grouping by moving to school districts with high average test scores.

"To see what is in front of one's nose needs a constant struggle." - George Orwell