Scoring Guide for the Mango Problem

Scores will be based upon the following:

POINTS

CORRECT ANSWER

4

Answer is correct: 18 mangoes

0

Answer is not correct (other than 18 mangoes)

 

POINTS

PROBLEM UNDERSTANDING
Understand the patterns, concepts, and approach

4

Shows correct understanding of the concept of fractional parts.
Shows understanding that each member of the royal household took a fraction of the remaining mangoes as opposed to the original number of mangoes.
Recognized a pattern in the number of mangoes taken. Each person (dog) took the same number of mangoes.

3

Understands the concept of fractional parts.
Understands that fraction is a part of the remaining mangoes.
Fails to mention that every person took the same number of mangoes.

2

Understood the concept of fractional parts.
Fails to show that each person took a fraction of the remaining mangoes, as opposed to a fraction of the orginal number of mangoes.

1

The task is misunderstood
Concept of fractional parts is applied incorrectly

0

No attempt at response

 

POINTS

STRATEGY
Choose and apply a valid strategy

4

Choice of a valid strategy: visual representation, guess and check, or working backwards
Applied the strategy correctly and completely
Provided rationale for choice of strategy over other strategies.

3

Choice of a valid strategy: visual representation, guess and check, or working backwards
Applied the strategy correctly and completely

2

Strategy was partially or incorrectly completed.

1

Strategy did not apply to this problem.

0

No attempted strategy

 

POINTS

COMMUNICATION
Explain the reasoning at each step, using pictures, symbols, and labels

4

Described strategy and solution clearly and completely, step-by-step
Correct presentation of solution, including appropriate labels, terminology, and symbols

3

Generally described strategy and solution clearly, step-by-step
Followed directions for presenting solution, including appropriate labels, terminology, and symbols, but not as clearly as a 4, above.

2

Strategy was described, but steps may be missing
Labels may be missing or directions may not have completely followed

1

Strategy was not explained according to directions or reasoning is confusing.

0

No attempt to explain

 

POINTS

REASONABLE RESULT
Review the work and show why the result is reasonable

4

Review used a diffferent approach to support the result
Review demonstrated correctness of work (show work)
Explained why the result makes sense

3

The problem was reworked using the solution to check its accuracy.

2

The check for reasonableness was not complete

1

The check for reasonableness was not valid.

0

No attempt was made to demonstrate the reasonableness of the result