Applying concepts from lower grades, the author applies whole-group differentiation concepts to middle and high school, showing teachers how it is possible to differentiate within the whole-group setting in which many educators are comfortable. By allowing everyone to participate in the same activities at different levels of complexity or mastery, the book offers all students ways to join in and experience success. These strategies raise thinking to a higher level, give students choices regarding how they demonstrate their learning, and invite a range of responses. The author supplies specific ideas for assessment before, during, and after instruction, so that the teacher can adjust to meet class needs. Five chapters include: (1) Student Engagement Window; (2) Questioning Window; (3) Flexible Grouping Window; (4) Ongoing Assessment Window; and (5) Getting Started. Reproducibles, Recommended Resources (Print and Web Sites), and an Index are included.