Zearn Math Grade 3, Mission 2: Place Value, Mass, and Capacity
In this unit, your child measures time to the minute, mass in grams and kilograms, and liquid volume in liters, then uses place value to round those measurements and to add and subtract within 1,000. It takes a break from the multiplication facts of the last unit, and the next unit returns to them with the 0s, 1s, and harder 6s through 9s.
By Robert “Bobby” BarnettMath teacher, parent, and founder of Bobby’s Math Club
What is my child learning in Mission 2?
- Rounding measurements and other numbers to the nearest 10 or 100, such as 152 grams to 150 grams or 200 grams. Learn more: Rounding to the nearest 10 or 100
- Adding and subtracting measurements and other numbers within 1,000, regrouping, or trading tens and hundreds, when a place needs it. Learn more about adding within 1,000: Adding within 1,000 · Learn more about subtracting within 1,000
- Telling time to the minute on a clock with hands and finding elapsed time, the time that passes, with a number line. 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 reading the marks on scales and containers. Learn more: Weighing things and measuring liquids
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
What is 43 rounded to the nearest 10?
- 50
- 40
- 30
How you can help
- Read the grams on food packages together, such as a 340-gram jar and a 454-gram box, round each to the nearest 10, and add to estimate the total.
- Ask your child to read the clock when an activity starts and ends, like 4:15 and 4:52, and find how many minutes passed.
- Fill a 1-liter bottle at the sink and pour it into a bigger container, counting the liters, then ask how many more it would take to fill it.
Where kids can get stuck
- Misreading the hour hand when it is close to the next number, so 4:55 is read as 5:55.
- Reading each mark on a scale as 1 gram when each mark stands for 10 grams.
- Looking at the wrong digit when rounding, such as checking the ones digit to round to the nearest hundred.
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
- place value
- The value a digit has because of its place, like the 4 in 470 meaning 4 hundreds.
- round
- To change a number to a nearby, friendlier number, like 47 to 50.
- minute hand
- The long hand on a clock that points to the minutes.
- elapsed time
- How much time passes from the start of something to the end.
- mass
- How heavy something is, measured in grams or kilograms.
- 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.
- liter
- A unit of liquid volume; a large water bottle holds about 1 liter.
- liquid volume
- How much liquid a container holds, measured in liters.
Ready to build your child’s confidence with time, mass, and rounding?
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 Zearn Math Grade 3 Mission 2 cover?
Zearn Math Grade 3 Mission 2 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.