Odd or Even
Determine whether a group of objects (up to 20) has an odd or even number of members
What a learner can do afterwards
- Pair objects and determine whether there is one left over (odd) or not (even)
- Count a group by 2s to determine if the total is even
- Write an equation to express an even number as a sum of two equal addends (e.g. 8 = 4 + 4)
The lesson
A group of things is even if you can put it into pairs with none left over. It is odd if one thing is left over with no partner.
Zoe has 10 buttons. She pairs them up: 2, 4, 6, 8, 10. Every button has a partner, so 10 is even. She can also write it as 5 + 5.
Fast check: count by 2s. If you land exactly on the total, it is even. If you have one left over at the end, it is odd.
Even means everything has a pair. Odd means one thing is left alone.
Watch it
Where it sits
This opens up
Nothing builds on it yet.
Where this leads
Jobs that lean on this skill. Follow one to see everything it is built on.
8 questions wait behind this lesson, each with its answer explained. Every answer feeds the sky: stars light as they are learned, and dim when it is time to come back.