This very complete and practical book is a great resource for the primary multiage classroom. R. Yates Creative Teachers, Creative Students by John Baer, 1997. This book is an excellent introductory resource on engendering creativity in your classroom. Although Creative Teachers, Creative Students has recently gone out of print, ordering it will enable you to find a used copy. Responding to the Needs of All Learners by Carol Ann Tomlinson, 1999.
All classrooms are full of diverse groups of students.
This is one of the most thoughtful and practical education books I have read. The author draws on a unique set of resources which I found to be both convincing and refreshing. This is an excellent guide on how to teach math in a multiage setting. The book provides an organizational framework, allowing you to still use the text and materials your school already has. It includes continuums for five strands of math and samples of the type of work students should be doing.