Mrs. Stapler

I can subitize groups of 5, then make groups of 5 with the leftovers… and there was one left.

Spoiler alert! Here’s the rest of my comment. Paying attention to units (mph vs hr) also helps clarify things here. SMP 6, attention to precision, is especially important when decontextualizing and recontextualizing. (Note: “she” refers to Jessica.)

Ready for the answer? Spoiler alert! … It doesn’t really mean anything, because the variable J in this equation wasn’t precisely defined. Here’s the first part of my comment to the person who posted this method: Upon further reflection…

My first thought:

Happy with my work, I submitted and refreshed the page. Some other teachers had posted their solutions. Some were variations of one of mine, but then I saw this (doing my best to maintain anonymity here):

Spoiler warning! Here was my idea… Switching from Jessica’s speed to Janine’s speed wasn’t very interesting (it basically just shuffled some terms around). But then it occurred to me there was another unknown quantity here: time. Check out how that went:

Since it was in a middle school math group, I added some tie-ins to middle school math standards, too. Math builds!

A few other teachers had shared the answer, but you know I love problem-solving and connect everything back to teaching, so I explained my whole process, along with tie-ins to SMPs as they came up (see the pics if you’re curious - spoiler alert):

Here’s the overall picture of my work. You have to explode my #3 after my #1 and #2 for it to go through the exploded pillars and hit the ones it needs to hit. My #4 also needs to explode after my #2 for the same reason. But I think #5 could go anywhere in the order.

(12) After removing the pillars that the third charge would explode, and removing two more orange dots that were no longer needed (since the 3rd charge had blown up the last remaining pillars in its column), there were 2 charges and 4 orange dots remaining, and it was easy peasy!