So here's a feature: the WCYDWT lessons that got away from me. It's important to me you know that for every WCYDWT lesson I spitshine and post on this blog there are dozens that never got off a list of ideas I keep and several more that got off the list and didn't pan out. This is my eulogy for the latter group, but don't mistake these posts as accidents of my curriculum development process. They are the process itself. If I don't chase these paths all the way to their conclusions, I'm pretty sure I'll stop seeing them altogether.
For instance, here's a picture of the menu of my favorite coffee shop, Red Rock Coffee.
Here's a reconstruction of the menu. (Click for higher resolution.) Notice the description of the last drink. "The most caffeine for your money."
This is pretty great. You have a ton of data on the board: ounces and shots and price. Have your students write some ideas down about how best to measure "the most caffeine for your money." Obviously dollars and shots need to figure in there somewhere, but you probably ought to divide the dollars by shots and then by ounces because one shot poured over twelve ounces of milk has a different effect than one shot poured over twenty ounces of milk.
Reagan : Russians :: Me : Coffee Shop Proprietors. "Trust but verify."
And would you look at those lying liars? You get more shots for less cash poured over fewer ounces with a large Cafe Americano — not with the advertised Red Eye. "Math exposes corrupt marketing" is one my favorite angles on mathematical investigation.
It Got Away
Except my wife pointed out to me that the Red Eye isn't a shot poured over water (like the Americano) or milk (like the latte). It's poured over coffee. It's caffeine poured over more caffeine. Which sunk my battleship.
Just watch your step, Red Rock Coffee.