Anchor paper 481
Anchor Papers:
Problem Solving
expert
Problem Solving Rationale
<p>The student's strategy of making a table of the day, puzzle pieces and total puzzle pieces works to solve part of the task and arrives at an answer by applying subtraction. The student's answer, "the answer is 5 puzzle pieces," is correct. The student shows evidence of analyzing the situation in mathematical terms. The student explores the numbers in the ones place and determines that a total of 150 pieces is not possible.</p>
Reasoning and Proof
expert
Reasoning Proof Rationale
<p>The student demonstrates correct reasoning of the underlying concepts of the problem. The student organizes and determines a total of 145 puzzle pieces are used in three days. The student finds the number of remaining puzzle pieces needed to finish the puzzle by applying subtraction. The student explains the phenomenon of how some sets of numbers can not have a total with a zero in the ones place. The student uses that thinking to explain how they realized that five puzzle pieces must be missing.</p>
Communication Level
practitioner
Communication Rationale
<p>The student correctly uses the mathematical term <i>day</i>, from the problem. The student also correctly uses the mathematical terms <i>ones place</i>, <i>dozen</i>.</p>
Connections Level
expert
Connections RationaleAnchor paper 481
<p>The student makes the Practitioner connection, "I know 36 is 12 + 12 + 12, 3 dozen." The student makes an Expert connection by extending their understanding of this task to place value. "Look at the ones place 36 + 41 + 68, 6 + 1 + 8 = 15. It can't be 150. So + 5 pieces gives the zero. 36 + 41 + 68 = 145, 145 + 5 = 150."</p>
Representation
practitioner
Representation Rationale
<p>The student's table is appropriate to the task and accurate. All labels are included and the data is correct.</p>