*Author: Wayne Smith*

Our group includes:

Geoff Busby- Timberline Middle

Nita Wood- Timberline Middle

Erin Barlow- Lehi Jr.

Melissa Cossey- American Fork Jr.

Wayne Smith- American Fork Jr

The first area we picked was in chapter 2, the percent chapter—specifically we picked percent change problems. We built the entire unit around an introduction using bar models and a visual concept of 10%. Much of our discussion has been around the proper uses of bar models in helping students understand integers, percent’s, equations and ratios. Bar models are not a one and done concept. We are trying to find ways to use them throughout the year to aid in a visual understanding of many of the 7th grade concepts, such as understanding positive and negative value, including absolute value. Also, the bar models are excellent for helping to understand ratios and proportions. There is real power in learning using the Bar Models. We first heard about their use from the Singapore Math concepts found in the Singapore elementary books. Now we are using those ideas on a middle school level.

Our unit was built around this first lesson that starts with this question:

Next we used the ideas to start doing routine percent problems like:

**This was followed up with problems that required more thought, for example:**

This was all in preparation for teaching our original purpose:

**With the bar model approach, students could now logically, pictorially and algebraically do many kinds of percent change problems.**

__Percent Change.__

**About the author:**Wayne Smith teaches math at American Fork Junior High School in the Alpine School District. He is the team leader for the 7th grade math teachers, wsmith@alpinedistrict.org