One of the best resources I've found this year is Differentiated Assignments: Helping Students Show What They Know, by Patricia Pavelka (Husky Trail Press). The book gives specific ideas to use when giving assignments to your students. Instead of planning 3-4 different assignments for the different levels in your classroom, you are planning one assignment that can be completed by all in a variety of different ways.

Instead of using workbook pages, author Pavelka suggests using magazine pictures for tasks. Magazine pictures involve choice, are motivating, and requires students to use higher level thinking. For example, when working on nouns, students choose a photograph and list all the nouns they see in the picture, or nouns their picture brings to mind.

I used calendar and magazine pictures, but you could also use pictures off the internet. Here is a site that might be good.

http://www.akidsphoto.com/botanical/flowers/index.html