Find how much longer
Comparing lengths lets your child answer real questions with numbers they measured themselves, turning measuring into a subtraction problem. It also builds careful habits, like measuring both objects from zero with the same unit. Comparing measurements comes up again in 3rd and 4th grade, including lengths with fractions of an inch, and in everyday questions like how much your child has grown since last year.
In this video, your child will learn to find how much longer one thing is.
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 much longer is the pencil than the crayon?
Example 2
How much longer is the ribbon than the straw?
Your child's turn
How much longer is the straw than the pencil?
The three key steps
- 1Measure both things.
- 2Find the part that sticks out.
- 3Say the unit.
Mistakes to listen for
- Adding the lengths instead of subtracting, answering 12 inches for how much longer a 7-inch pencil is than a 5-inch marker.
- Measuring one object in inches and the other in centimeters, then subtracting as if the units matched.
- Giving the longer object's length, 7 inches, instead of how much longer it is than the shorter one.
The lesson shows every step, so your child sees why it works. Read our parent's guide to measuring how much longer one thing is →
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 how much longer one thing is, 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 how much longer one thing is 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 how much longer one thing is
Questions at your child's level, about five minutes a day, on measuring how much longer one thing is and whatever PK-5 skills they need to develop. Unlimited practice, free forever.
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