Mass and Volume — Answer Key
Part A: Fix the Sentence
Each sentence has an error. Rewrite it correctly on the line.
1. Fix the sentence:
An apple has a mass of about 100 kilograms.
Corrected: An apple has a mass of about 100 grams.
Small objects like apples are measured in grams, not kilograms.
2. Fix the sentence:
A Grade 3 textbook weighs about 1 gram.
Corrected: A Grade 3 textbook weighs about 1 kilogram.
Larger items like textbooks are measured in kilograms, not grams.
3. Fix the sentence:
A Grade 3 student's dog has a mass of 10 grams.
Corrected: A Grade 3 student's dog has a mass of 10 kilograms.
A dog is heavy, so we measure its mass in kilograms.
Part B: Fill in the Blank
Write the missing word or number on each line.
1. One paperclip has a mass of about 1 gram in Grade 3 science.
A paperclip is tiny and light, so its mass is 1 gram.
2. A bag of flour at the store has a mass of about 2 kilograms for Grade 3.
Kilograms measure heavier items like bags of flour.
3. The unit gram is written with the short symbol g in Grade 3.
Grams are abbreviated as g in measurement.
4. The unit kilogram is written with the short symbol kg in Grade 3.
Kilograms are abbreviated as kg in measurement.
Part C: True or False?
Read each statement. Circle True or False.
1. A Grade 3 toothbrush has a mass of about 20 grams.
True False
Toothbrushes are light, so about 20 grams is correct.
2. A Grade 3 backpack full of books has a mass of 5 grams.
True False
A heavy backpack has a mass of several kilograms, not 5 grams.
3. In Grade 3, 1 kilogram equals 1000 grams.
True False
Kilo means 1000, so 1 kilogram is 1000 grams.