Zearn Math Grade 1, Mission 3: Ordering and Comparing Length Measurements as Numbers
In this unit, your child orders objects by length, measures with same-size units, and compares measurements as numbers. They also organize data in simple charts and ask how many more. This follows the unit on place value and adding within 20 and leads into place value, comparing, adding, and subtracting to 40.
By Robert “Bobby” BarnettMath teacher, parent, and founder of Bobby’s Math Club
What is my child learning in Mission 3?
- Ordering three objects by length and using one object to compare two others that cannot be placed side by side. Learn more: Ordering three things from shortest to longest
- Measuring length with same-size units laid end to end, without gaps or overlaps, and comparing the counts. Learn more: Measuring length by lining up same-size objects
- Collecting data, sorting it into up to three groups, and finding how many more or fewer one group has. Learn more: Sorting, tallying, and reading simple charts
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
Which object is usually the longest?
- A book
- A bus
- A shoe
How you can help
- Measure three stuffed animals with the same blocks laid end to end. Ask your child to order them and say how many blocks longer the biggest is.
- Use a ribbon to compare the width of your bed and the couch, then decide which is wider without moving them.
- Ask everyone at dinner to pick a favorite: morning, afternoon, or night. Help your child tally the answers and compare the groups.
Where kids can get stuck
- Leaving gaps between units when measuring, so the object seems shorter than it really is.
- Comparing ends without lining up starting points, so a lower object seems shorter.
- Adding two groups when the question asks how many more one has than the other.
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
- length
- How long something is from one end to the other.
- longer
- Having more length than something else.
- shorter
- Having less length than something else.
- measure
- Find out how long or big something is by counting units.
- length unit
- A same-size object, like a paper clip, used again and again to measure.
- gap
- An empty space left between objects when measuring.
- overlap
- When objects lie on top of each other instead of end to end.
- data
- Facts or numbers that are collected, like everyone's favorite fruit.
- how many more
- Words that ask for the difference between two amounts.
Ready to build your child’s confidence with measuring length?
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 1 Mission 3 cover?
Zearn Math Grade 1 Mission 3 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.