Illustrative Mathematics Grade 3, Unit 6: Measuring Length Time Liquid Volume and Mass
In this unit, your child measures in many ways. They measure lengths to the nearest half and quarter inch and show data on line plots, tell time to the minute, solve elapsed-time problems, and measure liquid volume and mass. Fractions from the last unit help with rulers, and the next unit turns to shapes and the distance around them.
By Robert “Bobby” BarnettMath teacher, parent, and founder of Bobby’s Math Club
What is my child learning in Unit 6?
- Telling time to the nearest minute and solving problems about start time, end time, and how long something lasts. Learn more about telling time to the minute: Telling time to the minute · Learn more about working out how many minutes have passed
- Measuring mass in grams and kilograms and liquid volume in liters, and solving story problems with those units. Learn more: Weighing things and measuring liquids
- Measuring to the nearest half or quarter inch with a ruler and showing many measurements on a line plot. Learn more: Measuring to the nearest quarter inch
Sample questions to try together
These are real questions from our practice. Tap the speaker to hear one read aloud, or the light bulb for a hint, and talk about the answer together.
Question 1 of 3
The school play starts 20 minutes after the time shown on the clock. What time does the school play begin?
- 6:25 p.m.
- 7:05 p.m.
- 7:00 p.m.
How you can help
- Ask your child to read a clock with hands at bedtime and tell you the exact minute, then how long until lights out.
- Hold up two packages, such as a 1-kilogram bag of rice and a 250-gram box, and ask how many boxes would match the bag (4).
- Measure toy cars or pencils to the nearest quarter inch and mark each length on a line plot you draw together.
Where kids can get stuck
- Measuring from the end of the ruler instead of the 0 mark.
- Reading 2:50 as 3:50 because the hour hand is close to the 3.
- Using kilograms for a light object, saying a pencil weighs about 5 kilograms.
Practice makes perfect
Bobby's Math Club has practice problems that adapt to your child’s level, each with a detailed explanation and an easy-to-follow video, so your child can build confidence in these skills one step at a time.
Words your child will hear
- elapsed time
- How much time passes from the start to the end of something.
- mass
- How heavy an object is.
- gram
- A small unit of mass; a paper clip is about 1 gram.
- kilogram
- A unit of mass equal to 1,000 grams; a big dictionary is about 1 kilogram.
- liquid volume
- The amount of space a liquid takes up, often measured in liters.
- liter
- A unit of liquid volume; a large water bottle holds about 1 liter.
- line plot
- A number line with X marks above it to show how many times each measurement appears.
- quarter inch
- A fourth of an inch, the length between the smallest marks on many rulers.
Ready to build your child’s confidence with measuring length, time, and mass?
In Bobby's Math Club, your child practices these skills at just the right level, with a hint when they need one, a clear explanation after every question, and kid-friendly videos. Unlimited practice is free.
Join the club
Written by Robert “Bobby” Barnett
Bobby is an award-winning math teacher, the author of Meet Every Learner’s Needs, and the father of two elementary-school math learners. He uses Bobby’s Math Club with his own kids a few times every week. Learn more or contact Bobby.
Which math standards does Illustrative Mathematics Grade 3 Unit 6 cover?
Illustrative Mathematics Grade 3 Unit 6 covers these math standards. Each one links to what it means, sample questions, and teaching strategies.
For teachers: Unit names and order vary between editions and districts, so your school’s own materials have the exact sequence. Learn how Bobby's Math Club can help your students grow.