## Wrapping up Inequalities

Today we went over any questions from the hw, then I had the kids stand up at their tables and in their groups of 4 line up, from left to right, from shortest to tallest. Then I “changed the rule” and said tallest to shortest, and they switched places. Then I “changed the rule” and had them line up from youngest to oldest, left to right. Then the whole class lined up in height order around the classroom. Finally I asked them what would be the easiest way to have them line up the other way in height order, and all 3 classes said “Just walk half way around the class.” Cool! I told them to remember they had to change their positions when I changed the rules on them, and now we’d do the math. We did a few equation examples, multiplying or dividing by positive and negative numbers and saw that everything was still true. Then we did a couple of inequality examples multiplying and dividing with positive numbers…then I had them multiply both sides of the inequality by -2, and just write the new “numbers”. They looked at it and saw if they just brought down the symbol the inequality wouldn’t be true. We talked about how with inequalities there is a relationship, and we had just changed the problem from positives to negatives, we’d “changed the rules” so therefore to keep the relationship true we had to change the direction of the inequality symbol. We did another problem dividing by -3, and I think it was clicking with a lot of them. We then did a few problems on the FACEing math page with negative variables, and showed how we were changing the problem – the negative had been on the left (-3x > 12), then changed to the right (x < -4), so the relationship with the symbol had to change too, to keep it true.

We’ll see tomorrow if the lesson was as good as I hope. I do think lining up in their groups and then rearranging was helpful (or at least fun!).