Primary+Round+1+May+2013

= Primary Round 1 = You paid $10 for something and got back 1 bill and 7 coins in change. How much could it have cost? Source: Marian Small - Past Presentations and resources []

Questions To Consider
As you view the student thinking about the problem consider 2-3 of the following questions to focus on. Please __**join this wiki**__ to share your thinking to the posted questions or a sample of a student solution on a division page. When you request to __**Join Now**__ (top left of menu bar) please identify your board, role and grades you teach, or are responsible for.

Solution A: []

What does the student know/understand? Pat: The student demonstrates good number sense when verbalizing the steps taken to solve the problem. I wonder what this student understands about estimating? Did the student know the answer wasn't correct when he said the amount spent is, "about"?

What strategies does the student use to solve the problem? What additional strategies should the student consider? Pat: The student uses logical reasoning and visual representations, [pictures]. I would encourage the student to use manipulatives such as base ten blocks or play money.

What probing questions would you ask the student? Pat: I would ask the student what other strategies or tools could be used when working to solve this problem.

What scaffolding questions would you ask the student? Pat: I'd ask the student the following questions: 1."When talking about the change you'd receive why did you pick a $5.00 bill?" and / or 2. "I see you were using subtraction to find the answer, is there another operation you could have used? How would that look?" and / or 3." I heard you say the seven coins,were pennies and when taken away from a dollar you said there would be 93 cents left. Please tell me why you took seven pennies away from a dollar. Where did the dollar come from?"

What feedback would you give the student? You might consider focusing on the mathematical processes or the student’s next steps. Pat: I would say, "I am curious about why you said, "It would be about $5.00 and 97 cents." Why did you use the word __about?"__

What are your next steps for instruction? Pat: Next steps would involve modeling or working collaboratively, using base ten manipulatives or play money to solve the problem.

Solution B: [] What does the student know/understand? Pat: The student understands that to find how much was spent, the difference between the original amount and the change must be found. The student knows the purpose of the operation of subtraction.

What strategies does the student use to solve the problem? What additional strategies should the student consider? Pat: The student used pictures. I would encourage the student to use manipulative such as play money or base ten blocks.

What probing questions would you ask the student? Pat: "How did you decide to draw a five dollar bills?" "How did you decide on the value of the coins? How much is each coin worth?" "Why did you decide to subtract 7 coins from the $10.00?"

What scaffolding questions would you ask the student Pat: "When I watched you solve this problem, I think you were saying that each coin was worth one cent. That means seven coins would equal seven cents a or seven pennies. How could you show how many pennies would be needed if you wanted to show the value of a loonie? "Now that we see how many pennies make up a loonie is there a quick way to find out how many pennies make up a twoonie?" "How many twoonies would we need to add to get ten dollars?" "Now that we see how many pennies make up a twoonie and how many twoonies make up ten dollars, is there a quick way to find out how many pennies make up a ten dollars?"

What feedback would you give the student? You might consider focusing on the mathematical processes or the student’s next steps. Pat: "You used pictures to solve the problem, what else could you use?" " How might using a manpiluative such as play or real money help you check your answer?"

What are your next steps for instruction? Pat: Next steps would involve modeling or working collaboaratively, using base ten manipulatives or play money when solving the problem.


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