Teaching rounding is a vital skill for understanding place value.
In Montessori we have lots of maths activities that naturally lend themselves to teaching about rounding. You may have been implicitly teaching rounding however it is important that like all maths concepts we bring the key concept to the foreground and explicitly teach how to do it.
If you are going to be teaching rounding of a 2 digit number then the child needs to be able to confidently read the written numeral and understand how it is made e.g. 25 has 2 ten bars and 5 units or a 5 colored bead bar. The same goes for higher numbers for example if you are teaching rounding of a 4 digit number then the child needs to be able to confidently read the written numeral and understand how it is made with the golden beads or stamp game.
Rounding needs to be done in a context so children can understand its point. For example simply saying to a child: "What number could 56 021 round to?" is not helpful as the child has no point of reference. A better question might be is 56 020 closer to 56 000 or 57 000?
Quick and Easy ideas to Teach Rounding
- Get a short bead chain. Have a child place down a certain number tag and then having the child say whether the number is closer to x or y and how they can tell by using the bead chain.
- Give the child a number of coins of your currency and have them round to a certain number e.g. $1 or a ten-cent amount.
- Use a number line. A number line is simply a piece of paper with one number on one end and another at the far end for the child to see how numbers relate to each other.
The Power Of Open-Ended Questions
Open-ended questions are great to encourage students to think beyond one correct answer. It is quite easy to take a traditional closed question and turn it into an open-ended question. Take these two for example:
Closed Rounding question: Is 643 closer to 640 or 650?
Open Rounding question: Write some numbers that could be rounded to 100. Explain how you got your answer.
The great thing about open questions is it means that you can see what strategies a child is using and can also see how fluent they are at explaining their answer to others.
I've made my own rounding set which includes closed and open questions. You can get a freebie set sent to your inbox
Download 80 rounding questions that utilise Montessori equipment with open and closed questions here.