Two-part metric measurement practice for Grade 5.
Try these before or after you print the worksheet. Every answer opens a table showing all four options converted to the same unit, because converting first is the whole trick. The last three ask you to put four measurements in order, smallest to largest.
Which is the most reasonable estimate for the length of a new pencil?
18 cm. A pencil is a bit longer than your hand. 18 mm would be shorter than a fingernail and 18 m is longer than a classroom.
| As written | In m |
|---|---|
| 18 mm | 0.018 m |
| 18 cm | 0.18 m |
| 18 m | 18 m |
| 1.8 km | 1 800 m |
Which is the most reasonable estimate for the mass of a bag of flour?
2 kg. A standard bag of flour is about 2 kg. 20 g is roughly a tablespoon of it, and 200 kg is heavier than three people.
| As written | In g |
|---|---|
| 2 mg | 0.002 g |
| 20 g | 20 g |
| 2 kg | 2 000 g |
| 200 kg | 200 000 g |
Which is the most reasonable estimate for the capacity of a kitchen sink?
20 L. A sink holds around 20 L, about ten large drink bottles. 200 mL is a small glass and 200 L is closer to a bathtub.
| As written | In mL |
|---|---|
| 20 mL | 20 mL |
| 200 mL | 200 mL |
| 20 L | 20 000 mL |
| 200 L | 200 000 mL |
Which is the most reasonable estimate for the width of a fingernail?
1 cm. About 1 cm across. 1 mm is the thickness of a coin and 10 cm is the width of your whole hand.
| As written | In m |
|---|---|
| 1 mm | 0.001 m |
| 1 cm | 0.01 m |
| 10 cm | 0.1 m |
| 1 m | 1 m |
Which measurement is the largest? The units are different, so convert before you compare.
0.5 km. Everything converted to m:
| As written | In m |
|---|---|
| 4 m | 4 m |
| 380 cm | 3.8 m |
| 4200 mm | 4.2 m |
| 0.5 km | 500 m ← largest |
Which measurement is the largest? The units are different, so convert before you compare.
3500 g. Everything converted to g:
| As written | In g |
|---|---|
| 3 kg | 3 000 g |
| 2800 g | 2 800 g |
| 3500 g | 3 500 g ← largest |
| 2 500 000 mg | 2 500 g |
Which measurement is the largest? The units are different, so convert before you compare.
1750 mL. Everything converted to mL:
| As written | In mL |
|---|---|
| 1.5 L | 1 500 mL |
| 1750 mL | 1 750 mL ← largest |
| 0.9 L | 900 mL |
| 1200 mL | 1 200 mL |
Click these in order, smallest first.
In m, smallest to largest:
| As written | In m |
|---|---|
| 250 mm | 0.25 m |
| 75 cm | 0.75 m |
| 2 m | 2 m |
| 0.5 km | 500 m |
Click these in order, smallest first.
In g, smallest to largest:
| As written | In g |
|---|---|
| 500 mg | 0.5 g |
| 40 g | 40 g |
| 0.2 kg | 200 g |
| 1.5 kg | 1 500 g |
Click these in order, smallest first.
In mL, smallest to largest:
| As written | In mL |
|---|---|
| 80 mL | 80 mL |
| 250 mL | 250 mL |
| 0.75 L | 750 mL |
| 1.2 L | 1 200 mL |
No buttons on these. Say your answer first, then check.
Why can 0.5 km beat 4200 mm even though 0.5 is a tiny number?
Because the unit matters as much as the number. 0.5 km is 500 m, while 4200 mm is only 4.2 m. A small number with a big unit can be much larger than a big number with a small unit, which is why you convert first and compare second.
What is the quickest way to compare 3 kg, 2800 g and 2 500 000 mg?
Put them all in grams: 3000 g, 2800 g and 2500 g. Choose whichever unit leaves you with the fewest awkward decimals. Going to milligrams works too but gives you seven-digit numbers to read.
Does a larger unit always mean a larger measurement?
No. 1 km is far bigger than 1 mm, but 0.001 km and 1 m are exactly the same length. The unit tells you the size of each step, not the size of the measurement.
Name something you would measure in millilitres, and something in litres.
Millilitres for a spoonful of medicine, a juice box or a test tube. Litres for a bottle of water, a bucket or a fish tank. The rule of thumb is that once you pass about 1000 mL it is easier to say litres.
Want it on paper? Download the free printable worksheet above: ten estimate questions, six comparison sets and an answer key that converts every option.