Math Expressions Grade 4, Unit 5: Measurement
In this unit, your child compares units of length, weight, liquid volume, and time, converts larger units into smaller ones, and solves measurement word problems. They also use formulas to find the area and perimeter of rectangles. It follows equations and word problems, which come in handy here, and comes before fraction concepts and operations.
By Robert “Bobby” BarnettMath teacher, parent, and founder of Bobby’s Math Club
What is my child learning in Unit 5?
- Converting larger units into smaller ones within one system, such as 5 pounds to 80 ounces or 3 meters to 300 centimeters. Learn more: Converting feet to inches and kilograms to grams
- Solving word problems about distance, time, liquid volume, mass, and money, and showing the amounts on a number line diagram. Learn more: Story problems about distance, time, and money
- Using the formulas for the area and perimeter of a rectangle, including finding a missing length when the area is given. Learn more: Using area and perimeter to solve real problems
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
Amara buys a 5-pound bag of oranges. How many ounces does the bag weigh?
- 60 ounces
- 21 ounces
- 80 ounces
How you can help
- Read package labels at the store: if a bag of flour weighs 5 pounds, ask your child how many ounces that is, knowing 1 pound is 16 ounces.
- Measure a rug or a table with a tape measure, then ask your child to find both its perimeter and its area, using the right units for each.
- Time an outing together: if you leave at 2:40 and walk for 1 hour 35 minutes, ask your child what time you will be back.
Where kids can get stuck
- Assuming every unit works in tens, so 1 hour becomes 100 minutes or 1 pound becomes 10 ounces.
- Multiplying the sides when the question asks for the distance around, which finds the area instead of the perimeter.
- Labeling area in feet instead of square feet, or perimeter in square units.
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
- convert
- To change a measurement to a different unit, like 3 feet to 36 inches.
- ounce
- A customary unit of weight; 16 ounces make 1 pound.
- milliliter
- A small metric unit of liquid volume; 1,000 milliliters make 1 liter.
- elapsed time
- How much time passes between a start time and an end time.
- mass
- How heavy something is, measured in grams or kilograms.
- area
- The amount of space inside a flat shape, measured in square units.
- perimeter
- The distance all the way around a flat shape.
- square unit
- A square with sides 1 unit long, used to measure area, such as a square foot.
- formula
- A rule written with letters, such as area = length × width.
Ready to build your child’s confidence with measurement and conversions?
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 Math Expressions Grade 4 Unit 5 cover?
Math Expressions Grade 4 Unit 5 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.