Last week my second graders and I spent our math instructional time trying out a new system for working through math story problems with a partner (Math Problem Solving in Context: Part 1). It was amazing! There were definitely some challenges for all of us but, in the end we persevered.
I introduced the Math Buddy Chat system to students on Monday. We worked with our math buddies to figure out the number of family members that would be attending our upcoming Wax Museum. Step 1 (independently read the problem, identify important words and numbers and underline the question) went smoothly for each group. Step 2 (Talk with your math buddy and make a plan to solve the problem and decide how you will show your work) really through them for a loop. They all wanted to start solving the problem right away. I helped them through this step by removing all writing utensils and they reluctantly discussed their plans.
This was a challenging problem because students had 14 numbers to deal with. Students used a variety of strategies to solve this problem and some chose math tools such as 100's charts, base 10 pieces and unifix cubes to do their figuring. When students finished step 3 (solve the problem on your own, double check your answer) they moved on to step 4 (check your answer with your buddy, if you got a different answer look to see what you did differently and rework the problem if necessary).
After the math buddies discussed step 4 the entire group took a look at each pair of students work and discussed which strategies they used to help them solve the problem. We began to notice that each group used more than one strategy to solve the problem. This entire lesson took one hour and twenty minutes.
The following day we used the Math Buddy Chat system again to figure out another problem that was important to us. We wanted to know how many packages of cookies we would need to purchase if each guest that came to our museum were to have two cookies each. Students had to figure out how many total cookies we would need and then figure out how many packages we would need if 10 cookies came in each package. This was a doozy and every single student (struggling to excelling) worked diligently until it was time for lunch!
The second lesson is where I imagined the input/output tables coming into play. After we looked at discussed each groups strategies I showed them how we could put the information into a table and then we named it. It was a brief, but powerful introduction.
Things I would do differently next time:
1. Introduce the Math Buddy Chat system with a simpler problem. Although my students persevered I think it would have been better if they had learned the system with an easier problem first.
2. When students are asked to do step 2, discuss the problem and come up with a plan, make sure they cannot write anything down. This planning part seemed to be difficult for them to grasp and every single one wanted to skip the discussion piece.
3. Have both partners explain what their plan is before they get started (just until we get the hang of this partnership thing).
And that is it. I learned a lot about my students understanding of place value during these lessons. I saw clear evidence that a student I thought had full understanding of place value still held some misconceptions and a student I thought did not really understand place value actually did!
Do you use a similar system for problem solving or have one that you think works well with second graders? If so I would love to hear about it!