I’ll be honest; I didn’t nail absolute value this year. I loved the activity and will do it again next year. However, in less than a month students totally spaced the rules we had covered. AND I had an uneasy feeling in my stomach with the thought of moving forward.

I put these up on the board today as review

Students has a solid understanding of the first two. Half the class could work through c then only a handful were correct on d.

This is a huge red flag, if I let the slide absolute value inequalities would be a train wreck. Here’s the deal; it would be an awful idea to move on and try and force feed the rules of absolute value inequalities. So, I decided to start from the beginning again.

Thankfully Fawn Nguyen has an awesome post on absolute value that was a life saver and here is how I worked through the lesson today.

We started with the idea of distance;

Then eventually added some notation to the thing. There were some great discussions on how distance is always positive and how to work around the whole -4 – 8 thing.

After this point I stopped and really drilled students on translating what the above statements were *actually *saying. More than just *“***The absolute value of negative six minus four is 10″** and asking students to think about this more as a distance thing.

**“The distance between negative four and six IS 10”**

My lesson on translating from earlier this year really helped when we jumped to this sorta thing:

The one issue I had here was it felt like students quickly shifted from thinking about absolute value as a distance to a rule where you take the number inside the absolute value and move 6 units to the left and right. Not sure what I think of that right now… I probably could have put more emphasis on translating but it just didn’t feel natural.

We practiced a few more of these then got into some interesting cases:

Tomorrow we are moving into absolute value inequalities continuing along with Fawn’s ideas. I really enjoyed this lesson!

*I missed my first post yesterday… I was out of the classroom again and driving for 9+ hours. 😦

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