this is an interesting point- one of the most discussed in education.
With the question of homogeneous (all of the same level) or heterogeneous (mixed) grouping, there really is no one “correct” answer.
But here’s one good idea that one school uses successfully (it’s used there for elementary children):
The classes are all mixed up level- wise, and with in the classroom, they use “chavrusos” and grouping VERY much. Meaning, the teacher will teach for 20 min about grammar, and then they will break into groups and do worksheets. Or for math review, they will do it together with a partner.
A few point about this system:
1. there are a few diff groups- sometimes they split up into the “yellow groups” and those groups are kids of all the same level, and sometimes when they break up into groups or partners, they are on different levels.
2. This system is excellent- because they pair/ group up different times with different people, no student is aware that “they” are the weaker students, and we are the smart ones.
3. This system also allows the teacher to work individually with one group at a time and give them individual attention they need for their studies.
4. It also enables them to review more. If the teacher wants them to review fractions, she can either spend 20 minutes, calling on different students for their answer. Or they can break into groups and either do a review sheet and when they review it in their groups they each say their answer- now in 20 minutes each kid has had 4-5 chances or they can play some math game in partners, and in 20 minutes, each kid has had 10- 15 chances!
Now that’s a lot more review!