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## Tuesday, December 14, 2010

### Review and Practice: Add Em Up

This worked really nice as a practice activity today, by my criteria of : the kids talk to each other, have ways to figure out if they're correct, and have ways to find their mistakes if they're not. I like when I can spend my time helping kids who need it and asking and answering meaningful questions, and don't have to hear "Is this right?" over and over.

The students got in groups of four, and each group got a total of 16 problems. Four pieces of paper with four problems each. The papers were different colors.

The students completed one problem on each page. So they all worked on one, rotated papers, worked the next one, etc. These guys even coordinated their calculators.

The paper color corresponded to the difficulty of the problems, which I let them know.

When all four problems were complete on a page, they added up their four answers. I posted the sums on colored index cards.

So if they check their sum and it's correct, great. But the best dialog started if it wasn't correct. Because first, they had to figure out which out of the four answers was wrong. And is it smart to start over and re-do the problem? Not in this case, since they were solving equations. It made much more sense to plug the answers in and see which one didn't work. Then they could start error-checking their work, which is great practice in itself.

The topic was solving exponential equations by changing the base, though this could work for anything. The document with the problems is available here. Enjoy!

1. Your checksum idea sounds fantastic!

2. Love this. Thanks for Sharing!

3. Very nice Kate. I'm working on optimization with my Calculus class. I think I'll give this activity a whirl.

4. I love this, too! And I am definitely using it. Something I am always trying to figure out when I do these types of cooperative activities, is what to do for the students who were absent. Do they just miss the activity altogether? Do you have a page of problems that they have to do on their own? I want to make sure everyone gets the same type of practice.

5. Hi Mrs G - Yes mostly they just miss the activity. If they are responsible for making up what they missed, and ask me about it or come outside of class, I use extra copies to work with them on practice. I'm sure responses would be different depending on the situation at a person's school. My school is on periods, so I see them every day, and attendance isn't a big problem.

6. love it! this is going into algebra 1 the day we get back!

7. This is amazing - I am definitely going to use it! Thank you for another creative idea

8. I teach fifth grade mathematics and language arts and I can see this working extremely well with layered lessons. Thank you for sharing.

9. As usual, the most glorious and original part of this idea is also the most fiendishly clever -- namely, the ways you weave in motivation for students to check their work (and each other's). I love this!

- Elizabeth (aka @cheesemonkeysf on Twitter)

10. I just tried this idea yesterday with my Geometry classes for test review day. It worked really well, even with a minimum amount of prep.

11. I just went through these problems because I'm a few weeks behind you in my Algebra 2 class. In addition to using a clever practice structure, this is also an excellent sequence of problems for this activity.