Measure with two different units
This is where your child discovers that a measurement needs both a number and a unit. Seeing that smaller units give bigger numbers is surprisingly important later: in 3rd grade the same idea helps with fractions, where more pieces in a whole means smaller pieces, and in 4th and 5th grade they convert between units, such as knowing that 3 feet is 36 inches.
In this video, your child will learn to measure with two different units and compare.
The lesson stops at each question for your child's answer.
Three problems, each a little harder
Each problem is worked step by step. Your child will solve the last one before Bobby shows how.
Example 1
How many paper clips long is the pencil?
Example 2
How many cubes long is the ribbon?
Your child's turn
How many cubes long is the straw?
The three key steps
- 1Measure with two units.
- 2Shorter units: you need more.
- 3Longer units: you need fewer.
Mistakes to listen for
- Thinking the bigger number means longer, so a book measuring 25 centimeters seems longer than the same book at 10 inches.
- Expecting a bigger unit to give a bigger number, so predicting more feet than inches for the same object.
- Writing a measurement without a unit, such as 25, so no one can tell if it means inches or centimeters.
The lesson shows every step, so your child sees why it works. Read our parent's guide to measuring in inches and in centimeters →
Is your child ready to practice what they've learned?
Bobby's Math Club offers unlimited practice for free.
Join the clubMore kid-friendly lessons
More 2nd grade Measurement & Data, with questions your child answers along the way.
Questions parents ask
Does my child need an account to watch?
No. You can watch this on any device at any time. If your child would like to practice measuring in inches and in centimeters, and you'd like parent-friendly reports on your child's progress and growth, you can join Bobby's Math Club for unlimited free practice.
What happens when my child answers a question?
A right answer gets a cheer, and the lesson carries on. If your child isn't sure, they can tap "I don't know yet", and Bobby gives the answer and shows another example. Nothing is scored or stored.
Is this the same lesson that's on YouTube?
Yes. Here, the lesson stops at each question and waits for your child to answer. On YouTube, each question stays on screen for a few seconds, and then the lesson plays on.
Where can I learn more?
There's a short, kid-friendly lesson like this one for every Pre-K to 5th grade math skill, all in our video library. Our parent's guide to measuring in inches and in centimeters has more on where kids get stuck and how you can help at home. In the club, your child practices at just the right level, about five minutes a day, and you get parent-friendly reports as they grow. Learn more about how it works →
Practice measuring in inches and in centimeters
Questions at your child's level, about five minutes a day, on measuring in inches and in centimeters and whatever PK-5 skills they need to develop. Unlimited practice, free forever.
Join the club