Criteria and Performance Level Rationales
Problem Solving
The student's strategy of creating a table of three teams of students and calculating the total seconds per team to determine if they are equally matched works to solve the first part of the task. The student's answer, "second Answer on my table," is correct. The student's answer, "41.7 s = 41.7 s," "41.7 s < 42.5 s," and "42.5 s > 41.7 s," is correct for the second part of the task.
Reasoning Proof
The student demonstrates understanding that Mr. Fair requires three teams of four students that are as equally matched as possible. The student also shows correct reasoning in her/his use of the less than, greater than, or equal sign to compare the total crab walk times of the three teams.
The student correctly uses the mathematical terms time, second(s) from the task. The student also correctly uses the terms table, total, key. The student correctly uses the notation 8.9, 10.3, 11.4, 12.2, 11.1, 8.7, 9.9, 10.9 from the task. The student also correctly uses the notation 42.8, 40.6, 42.5, 41.7, <, >.
The student makes the mathematically relevant observations, "Scorpions are 42.5 - 41.7 = .8 s slower (than Speedos and Intruders), and "Amy is really fast. 8.75 is faster than everybody else."
The student's table is appropriate to the task but is not accurate. The seconds listed in the "Time" column for Sally, "Mardeth," and Emily do not indicate a decimal notation. The last "Time" column lacks the s notation for seconds.