After developing my own program which you can read about in my blog thepopeof4th.blogspot.com, I found what works best for my 4th grade students. M.A.T.H. Station Rotations are a fabulous way to address all of your student's needs by personalizing and customizing instruction. All students meet with the instructor during whole group to receive what they need (ie. reteaching, extension learning, or in-depth practice with problem solving strategies).
This program would work well in any grade level. Make adjustments to fit the needs of your students and see them succeed and become confident in their math abilities!