I teach 3rd grade and I am not sure if I should start my students with Superspeed 100 or 1000. I am thinking at the beginning of the year I would start with 100, but I will have a few students who I think will "graduate" quickly. Any ideas?

I would start with super reader 100 but have 1000 ready to go because your students that are on grade level will finish with 100 quickly