I end the Physics 1 year with light and wave optics. Ray optics has been bumped to AP Physics 2. This helps to forestall the post-CST and post-AP doldrums that might otherwise take root. By the way, when students complain they can't do this or that because they suffer from Senioritis, I remind them that Senioritis is the disease, physics is the cure, and me? I'm the doctor!
Anyway, we get to rainbows, mirages, blue skies, 3-D movies and more during this season, so it's not so bad for anyone.
When we talk about diffraction, we end up doing an activity called "Diffraction in Action." (I know, too easy.) The activity ends with a pair of "rainbow glasses" being given to each student. Their experiences in the activity to this point allow them to see the glasses as crossed diffraction gratings.
But you'd think the Candyman had come to the room with delicious treats for the little boys and girls. Be prepared for squeals of delight and proclamations that this is the coolest thing ever and that they'll never take the glasses off.
To push the merriment over the top, I ask them to don the glasses and look toward my camera in the front of the room. When the flash pops, their collective shrieks are enough to provoke angry calls from the bowling alley, complaining about the noise we're making.
Worry not about any complaints from colleagues about the distraction that bespectacled students were in their classes. It's for science!
Of course, rainbow glasses don't grow on trees. You have to order them and pay for them. I get mine from Arbor Scientific for $0.75 each (volume pricing), so I can set up all my students for about $100. I've never been denied reimbursement from whichever funding source I've asked.
Blog of Phyz readers already know I'm a sucker for activities that get jaded high school seniors to act like elementary students--if even only for a little while. This active/giveaway meets that criterion with happiness to spare.
Diffraction in Action (PDF)
Diffraction in Action Answers (PDF)