They fairly quickly recognized that it was quadratic (not linear), but struggled with how to find the rule. We looked at the number of rows and the number of helmets in each row for steps 1 - 4 and then noticed a pattern:
They were a little less focused on the math today, compared to yesterday, with lots of students guessing as soon as the question came up <insert my sad face here>. Lesson learned - one Kahoot is plenty in one week!
The rest of the class was spent working on the quadratic handout from Monday or on this quadratics review sheet for those who had finished the previous handout.