Someone choosing cents/min implies he is looking for the cheapest way to get a fixed task completed. “I need 30 mins in this store, how can I park cheapest?”

Someone choosing mins/cent implies he is looking for the maximum time allowed for the change in his pocket. “I’ve only got 50 cents, how long can I stay at the park?”

I think it’s an interesting question (especially when applied to the American mpg vs the European liters/100km). It could also bring up the idea of multiplicative inverses mathematically.

Or to come at the the same issue from a less inflammatory hook: “Who cares about small change?” Why does the government pay such close attention to such small sums of money? Illustrates federal vs state vs local and leads into a discussion about the theory of laws like this one and why they exist.

Another humanities link, different direction. Put up alongside this one an image of the RFID-controlled parking meters that are the norm in many Asian countries (google image search – octopus parking meter – to see what we use in hong kong). “Why the difference?”

Could also do this one with any number of countries. Probably much harder to use this effectively in class…but it’s cool.

why?

The teacher doesn’t really remove themselves from the scene. You are critically important for setting up the story, and for setting the beats that move it forward.

But, if it’s a good story, the kids tell it themselves, and you get to hide in the shadows while they do it. If the teacher weren’t crucially important for that, textbooks wouldn’t suck.

Which reminds me: I’ve got about 40 lbs of nickels lying around here. I’m quite sure that there will be an opportune time to drop a big canvas bag of them on some poor kid’s desk at some point.

In a world where teachers, particularly those working in high needs areas, are constantly plagued by standardized test requirements time is not on our side and as such…we have to somehow drive the instruction according to some arbitrarily created calendar or pacing guide.

I’m very interested in your position on textbooks because, quite frankly, it mirrors my own. Textbooks are dull and they tell kids what, how, and when to think about a problem. I want to encourage my students to become thinkers but the materials…and subsequent assessments pull students back into the real of passive recipients of my instruction.

However, assuming that franchising education and allowing students to create their own context for a problem situation are not incompatible…how do we go about delivering this type of instruction while still meeting specific standards in a limited time frame ?

Or is the real answer to the problem…to change the standards to fit real learning ? Instead of arbitrary “grade level appropriate” content is the answer to place students, regardless of age, where they can best function in the curriculum ?

• Which coin is worth the most?
• Why would the meter have this disparate money-to-time ratio?
• Do the meter makers just not know math?
• What if there weren’t a one hour time limit?
• What if one quarter equaled two dimes and a nickle? Or one quarter equaled one dime and three nickles? Or five nickels?

The parking meter v. covered garage is useful in that it gets kids arguing feverishly but I can’t ignore the possibility that a class of 14-yo’s will have no opinion whatsoever on the matter.

Nickel: 2 1/2 cents/minute
Dime: 2 cents/minute
Quarter: 2 1/12 cents/minute

This reminds me of the duct tape picture and the nickel stealing vs. dime stealing.

You could take it in another direction and compare the parking meter to a monthly rate in a covered garage by converting to the same units. There’s some interesting trade-offs there between not having to feed the meter, convenience of having a reserved space, inconvenience of winding through a narrow garage, etc. The units could also be converted to $/hour and compared to minimum wage.

I suppose since the coins are discrete, you can do some combinatorial problems as suggested above.