Which number doesn't belong? This lesson requires students to think critically as they determine which number is not a factor of a particular number. Teach it on its own or as support for the lesson Factors Over the Rainbow.

Why make things harder on ourselves? Teach your students to decompose numbers to make math easier! Use this as a stand alone lesson or a pre-lesson for Decompose to Multiply: 6, 7, 8, and 9.