During a family game of Yahtzee last night, my 7 year old/1st grader and I had a brief conversation about addition/multiplication being commutative vs. not commutative (a concept she knew about), which led to telling her that negative numbers are a thing that exist, and I drew out a little number line from -10 to 10 and showed her 2 - 5 = -3. I thought nothing more of it.

This morning, in the middle of her pretend play, she starts reciting "2 - 5 = -3" on repeat so I ask her what 5 - 10 equals. Without hesitation, "-5!" "What's 10 - 11?" "-1!" "3 - 5?" "-2!" I completely wasn't expecting her to actually get it when I explained it over Yahtzee, I just wanted her to know it was a *thing*.