2.NBT.A.1- Understand Place Value (Flawed Reasoning)

Evidence Statement 3.C.4-7- Distinguish correct explanation/reasoning from that which is flawed, and, if there is a flaw in the argument, present correct reasoning. (For example, some flawed student reasoning is presented and the task is to correct and improve it)

Make a Number

Lola is trying to make the number with the least value using the digits 3, 4, and 5 only once. 

She said the number with the least value is 354.

• Lola is not correct.

• What is the number with the least value that she can make using all the digits only once?

• Explain how you know this is the number with the least value.

Enter your answer and explanation in the space provided.

Student Copy

Scoring Rubric

Score of 3 Points

Student response includes each of the following 3 elements.

• Reasoning component: Correct explanation of Lola’s error.

• Computation component: Correctly identifies the least number as 345.

• Reasoning component: Correct explanation of answer given

Sample Student Response: Lola’s answer is not correct because the 5 is not in the place with the least value, it is in the tens place instead of the ones place. You have to put the digits in order from least to greatest to make the smallest number. 4 should be in the tens place and 5 should be in the ones place.

Score of 2 Points

Student response includes 2 of the 3 elements.

Score of 1 Point

Student response includes 1 of the 3 elements.

Score of 0 Points

Student response is incorrect or irrelevant.