Angles are turns, measured in degrees
Understanding that an angle measures a turn, not the length of its sides, is the foundation for nearly all the geometry your child will meet. It is what makes a protractor reading make sense, and it shows up in everyday life, from a skateboarder's 180 to giving directions. Later this year they measure and add angles, and in middle school they find unknown angles in triangles and other shapes.
In this video, your child will learn to measure angles as turns, in degrees.
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 degrees is a quarter turn?
Example 2
How many degrees is a three-quarter turn?
Your child's turn
How many degrees is a third of a turn?
The three key steps
- 1A full turn is 360°
- 2Part of a turn: 360 ÷ parts
- 3Put parts together: add
Mistakes to listen for
- Thinking an angle with longer rays is bigger, even when both angles open by the same amount.
- Measuring angles in inches or centimeters, as if the length of the rays were what counts.
- Struggling to connect a quarter turn to 90 degrees and a half turn to 180, out of a full turn of 360.
The lesson shows every step, so your child sees why it works. Read our parent's guide to what angles are and how degrees measure them →
Is your child ready to practice what they've learned?
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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 what angles are and how degrees measure them, 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 what angles are and how degrees measure them 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 what angles are and how degrees measure them
Questions at your child's level, about five minutes a day, on what angles are and how degrees measure them and whatever PK-5 skills they need to develop. Unlimited practice, free forever.
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