M2.8.5 For the adult
Odd and even rules
Is 7 + 9 odd or even? Do I have to add them to know?
What this chapter teaches
An even number makes pairs with none left over, and an odd number has one left over. Odd plus odd is even, because the two left overs make a pair. One example that fails breaks a rule, but examples that work do not prove it.
Three questions to ask
There is no one right wording. Listen for the idea.
- Without adding, is 17 + 25 odd or even, and how do you know?
- Why is an odd number plus an odd number always even?
- Tariq tried three examples and they all worked. Is the rule proved?
After the chapter, the learner can
- Explain why odd + odd always makes an even number
- Test a rule with many examples before you trust it
What they copy into their notebook
Even numbers make pairs with none left over. Odd numbers have one left over. Odd + odd is even, because the two left overs make a pair. One example that fails breaks a rule.