It’s a shame that we’re just finishing up Quadratics Functions in my IB Math SL course today. After being pointed to the Radio Lab podcasts from NPR by my buddy Shane, I found this video on parabolas in the real world.
It would be interesting to start the unit next year by doing the same pendulum experiment, showing them this video and then discussing the imagery that is shown.
If you were going to center an entire unit on quadratics around a single concept/idea/question, what would it be? Using the MYP holy triumvarate of Significant Concepts, Unit Questions and Area of Interaction focus, this video compels me to think of universal laws (SC), “Why are parabolas used in art and architechture?” (UQ), and Human Ingenuity (AOI).
(For the non-MYP crowd out there, what would be your theme of your parabolas unit?)
You mean I can tag individual posts in my Google Reader? Why did it take me so long to see this? So, as I’m reading dy/dan or The Number Warrior or Math Stories and am inspired by their ideas, I can
immediately tag them with the appropriate class name so that I can find it again when I need it?
Did anybody else know about this? Master of the Obvious, indeed…
We’ve reviewed Cartesian coordinates, we’ve learned the distance formula, we’ve talked about transferring the Cartesian plane onto the surface of the Earth and coming up with latitude and longitude, we’ve studied SOH-CAH-TOA, we’ve talked about bearings, and we’ve found the distance between two points on the Earth using proportions and a bit of trig if necessary.
The Setup
I book two lessons in the computer lab. In that time, there are four tasks that need to get done:
We look at the idea of trilateration and how we can pinpoint an exact location using three circles. I’ve created a simple GSP activity to illustrate this.
With their new-found knowledge, the students get the chance to find a missing hiker, using page 2 of the same GSP file.
A simple WebQuest to learn about how GPS works.
Some problems for students to answer to reinforce.
GSP – Trilateration – (For some reason, I can’t upload this file. If you want it, let me know and I’ll email it to you.) gps-and-mathematics.doc
Check-up and Learning the Tools
The next class is spent clarifying any questions and making sure they can answer the questions in task four. We then spend about 30 minutes getting to know our GPS receiver. I have the Garmin eTrex Vista, so I downloaded a .pdf version of the manual and snipped out the relevant screenshots. We go over how to create and name waypoints, how to find waypoints, how to measure the distance between two points, how to use the compass, and any other questions that might come up.
The Field Work
Armed with our knowledge of how our GPS receivers work (I normally borrow as many as I can from other teachers) and divided into small groups, it’s time to get outside and do some GPS-ing.
I’ve come up with four challenges that increase in difficulty. They use their GPS receivers to take measurements so that they can find the distances later.
Using a right triangle to measure the distance across a ‘river’. I do this with each group, step-by-step to ensure they
Using a similar technique to check the length of our soccer pitch.
Use the law of sines (which I introduce them to but do not go over in any detail other than to present the formula) and given points to estimate the distance to a building off-campus.
Use any method to estimate the distance from our flag pole to a different building off-campus.
The groups can finish taking measurements for task 1 and 2 in a lesson. They then complete 3 and 4 during the next lesson.
Total time: 5 days (1 hour periods/day).
The students seem to enjoy the activity. Most of them have seen GPS systems (who hasn’t these days?) but have never actually used a handheld unit. None of them have ever used a compass to find direction. If you don’t have access to GPS receivers, you could probably get away with this activity using compasses and trundle wheels. But it won’t be nearly as cool…
immediately tag them with the appropriate class name so that I can find it again when I need it? 
