What math concept should an 8th grader master?

Linear functions — shhh...it's pre-algebra, and they've got to get this.
YouTube video

Bill Day teaches middle-school math in Washington, D.C. He received the 2013-14 Teacher of the Year award for the district.

Hear about a math concept he believes eighth graders should master to be successful in high school.

Video transcript

“In my eighth grade classroom, I really focus my students on understanding the concept of a function. In particular, focusing on linear functions where one quantity is related to another with some initial value and then a constant rate of change. For example, if a gym charges a registration fee of $50 and then $20 per month. If I gave that scenario to my students, I’d want them to be able to build a function that relates that registration fee as an initial value and then the monthly fee as a rate of change.”

Understanding and solving linear equations looks like this and this when an eighth grader does it.

Real-life problems look and sound like word problems. Can your eighth grader use linear equations to work them out like this?

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