It's even when I make it a decimal

Kristin (@MathMinds on Twitter) teaches fifth grade math. She and her students were making up number puzzles. One student—whom we have agreed to call "Billy"—made up an interesting set of clues. This led to a fun conversation between the two of them, which she shared with me on Twitter.


  1. Hmmm.... What does it mean to "make it a decimal"?
  2. This is great. Billy has an idea. He is building an argument. I try to state what I think his rule is.
  3. So this is your chance to play along. Head on over to our Google Form and submit your vote. Will Billy say 3.0 is even or odd? Be prepared to explain your answer!