In our Glencoe algebra textbook, *D*=*rt* problems are lumped in the same section as Mixture problems. I get it. And I don’t.

Maybe I’m kidding myself or in denial, but this year I’ve been saying this phrase a lot in class: Do what makes sense.

I’m tired of using tricks, mnemonics, pre-made grids to help kids learn. Like this question in the textbook. No!! I don’t want my kids to “copy and complete” anything!

So as we look at each D=rt problem, I’m asking the kids:

- draw a picture
- what do you notice?
- what else do you know just by looking at known information and the picture?
- what seems like a natural question to ask about this scenario?
- set up
*D*=*rt*for both items that are moving - which of the variables — D, r, or t — stays the same?
- we don’t know the distance traveled by each of the cars, but we do know total distance, so how do we express that?
- when we multiply these two quantities, what do we get? what does the answer represent? what’s the unit?

I had them whiteboard these problems. I stole the cartoon from Chris Hunter’s post (most awesome post, by the way 🙂 — but I had to do some caption edits.

I don’t know. I’ll see how they do in the next few days, but I really want the kids to make sense of problems from scratch, without any help from anything or anyone — just start something that makes sense!