1_22_07

Large group: (Heidi)
> > "Now I don't want you to say the answer or start to solve it. I just want you to think about //how// you are going to solve it. Will you use addition or subtraction?" Ask one or two people to share and tell why they will use that operation. Don't comment on their reasoning, but ask if any other students have comments about their thinking. > > "Ok, now I'm going to tell you the problem again and you may solve it. You can use a tool if you think you need to, and if you don't think you need a tool, then you don't need one." (Provide part-part-whole mats and cubes.)
 * 1) Review the Trading Game altogether and play a bit. Then they play in pairs.
 * 2) Last 15 minutes: return to solve a subtraction story problem and share strategies with a partner. "I'm going to tell you a story and I want you to make a picture of it in your mind so you can figure out what the operation is. Are you ready to see it in your mind? Here it is: Dana rolled 13 balls down a ramp. Afterwards he could only find 8 of them. How many balls got lost?"

Afterward, have them share with one partner how they solved it. They should ask each other questions if they don't understand what their partner did. Then they can share with the whole group, but they have to share how their //partner// solved it. The teacher models on the white board how to show those strategies on paper.

Small group: (Maria)
3. Say, "I'm going to tell you a story and I want you to make a picture of it in your mind. I'm going to tell it to you first without numbers, so you can decide what the operation is, if it's going to be addition or subtraction. Here it is: Jana rolled some balls down a ramp. Afterwards she could only find some of them. How many balls got lost?
 * 1) Ask, "How many groups of 10 and extras do you think there are in 25?" Write down each child's estimate. Then have them make 25 using penny strips and pennies. Figure out together how many groups of 10 and extras there were.
 * 2) Give each child a collection of beans to count and record how many groups of tens and extras there are.

"Is Jana going to have more balls at the end, or less balls than she started with? What is the operation? Are you going to add or subtract?"

Student answer, then tell the problem again with numbers.

"Jana rolled 11 balls down a ramp. Afterwards she could only find 3 of them. How many balls got lost?"

Have them solve it with cubes or however they choose. They show their work on individual white boards. Remind them to label their answer, write an equation, and show how they got the answer.