With the increase of diversity in classrooms and conflicting or confusing advice from experts, teachers may feel pulled in many directions as they race to cover the curriculum. Successfully meeting the challenge of teaching in diverse classrooms depends, in part, on using research-based instructional methods that boost academic skills and foster independent learning. The authors discovered and used several methods that produced significant student academic gains for all students in their classroom. This article describes one of those methods: teaching big ideas. Rather than placing the emphasis on exposing students to every objective or everything in a textbook, teachers might ask themselves: What are the one or two main ideas or core concepts from this lesson that all students should learn? In other words, what big ideas should all students learn today? (Contains 4 figures.)