From S Rea
Wow!! It sounds like you teach in the quintessential "one room school house"!! My first thoughts were that it would be a bit confusing to mix the two. Why not have all your various reading "groups" going on while the rest of the students are doing other D5 rounds, then switch to a math focus with the 3 areas while you meet with those groups?
However, your situation is so specialized, that I just bow to you to teach such a gemisch of children!!