In my quest to obtain continuing education units, I applied for and was accepted into the Exploratorium's three week
Teacher Institute! It's all about increasing engagement and curiosity in the classroom through inquiry activities. I describe it as science summer camp for teachers!
And seriously, I come home every day gushing to my husband about what we did and what I learned. I very much feel like a kid on Christmas morning running around with a bunch of new toys! The first week has focused a lot on perception (it's really flawed if you didn't already know), light, and optics. And just in the first two days I got to experience half a dozen activities that could have been beautifully integrated into my concluding unit this past year - would have made for a more student centered experience (something I always endeavor to do!).
We started with rainbows. Rainbows are easy enough to create with a flashlight and a prism, or better yet, sunlight shining through a window covered in
diffraction grating (it's not
that expensive).
There wasn't really an objective. Just a rainbow on the ground, white paper, markers of various colors, and directions to see what we could figure out. We drew squiggles and happy faces!
And when you drag a red object (or picture) through the spectrum, it looks red when you're in the red to yellow part of the spectrum, but when you get to green it turns black. And then when you arrive at violet it looks red again!
But the most exciting discovery was highlighters! I won't completely spoil it for you. Watch this video. (Videos definitely work in Chrome, but maybe not in Safari. I didn't test it in Firefox).
Isn't that cool?! The highlighter is not just a pigment that absorbs light! It is also an emitter of light if it gets excited enough! So it glows when you get to cyan or so! This helps it be more visible when you're reading in natural lighting.
Another cool thing - that's hard to see here because there are other sources of light in the room - but the highlighter continues to glow even after you move past the violet part of the spectrum!
Do you know what that means?! I have evidence that the spectrum continues beyond what I can see!!
And the most brilliant thing about this whole activity was there were no explanations of pigments, or light spectra. Just questions - what do you see? What does that tell you? What conclusions can you come to?
The explanations came later when we were all invested in understanding. Now of course, we were a group of science teachers who are definitely motivated to understand the natural world around us, and a significant majority of the group already understood exactly what was happening. But the point is to create a situation where students want to understand - that students are demanding answers.
More often than not questions were just answered with a, "I don't know. Let's try it and see!" or a "We have that exhibit!" (How cool would it be to just teach physics with an entire museum right behind you?!)
Then there was this gem:
What is that look like its a picture of? I mean, how many mirrors do you see?
There's only two. It's a plane mirror (regular old mirror) standing in front of a concave mirror. And the small one you can see is not actually there - it's just a reflection. But it's a reflection that looks like its actually there floating in three dimensional space in front of you. Your eyes can't tell the difference (and standing in front of it is eerie!).
So what did we do? We walked through the image of a mirror of course and then kept going past the focal point of the concave mirror. Here's another video. The camera shows exactly what I could see as I moved through it.
So what was the point of this other than being impressive? Well, we were learning to draw ray diagrams in actual space with metersticks. Of course we didn't call them ray diagrams until after the activity. But then when you teach students to draw ray diagrams they suddenly have a much better concept of what those ray diagrams represent. (And now I really really want to teach optics again!)
I figure I can make a small version of this two. Just need the two different types of mirrors, though a concave mirror might be a bit pricey... And an Alice in Wonderland Action figure of course! Or maybe a white rabbit!
We spent much of the week talking about the eye - how it works, how it receives and interprets signals, and how it lies to us. So then, what's the next step? Let's dissect an eye of course! Yes, this is physics, and not biology, but we can find the actual lens in an eye and demonstrate that it works the same way a glass lens does. We can show you that the little black dot in the center of your eye is actually just a hole behind the cornea that dilates to allow light to enter. We can find the iridescent screen on the back of the eyeball where images are projected.
Yeah, okay that's kind've gross. But in a really interesting kind of way!
Now, I haven't really learned any new physics myself in this program (which I assume is a good sign!). Really, I've just been learning how to show the phenomena in really simple ways so students can see and experience it. Or in some cases, how to build something that can show the phenomena (I've learning to use power tools and cut PVC pipe! But I'll maybe talk about that another day!)
It's been fun and exciting! And that sense of awe and amazement is something I feel like I haven't experienced inside the classroom in awhile. I have seen it in students and I always enjoy inspiring that feeling in others, but it feels good to be reminded of what that feels like myself too.
At the end of the day, we have to choose from three electives. And choosing is hard! There have been several days where I really wanted to go to two topics, and another day where I didn't really want to go to any of them. And I found myself wondering, should I go to the workshops on topics that I can incorporate most easily into my physics classroom and curriculum? Or should I go to the workshops where I'm the most personally curious? Go to the biology and chemistry workshops where I don't already know all the science?
I eventually came to the conclusion that I probably should participate in some of both! I want the activities to bring to my classroom, but I also want to be excited about learning cool science!
Friday, I decided to go the the Etching workshop. Etching refers to printing or engraving a design or pattern onto an object. We were specifically learning how to remove the topmost layer of a piece of stainless steel using a saltwater solution and a battery. This is actually a chemistry topic, but I wanted to learn how to etch! Sounded artsy! The technique is pretty simple!
First you put your design on the piece of steel. We used electrical tapes and/or paint pens to put designs onto dog tags.
We used a 9 Volt battery and connected the positive terminal to the piece of steel and the negative terminal to the end of a q-tip. The q-tip is saturated in the salt water (we used pickling salt, which is pure NaCl and apparently works better). Then you basically just dab around the edges of your design. It will sizzle and the q-tip will turn yellow/black, which is the metal you have removed. This apparently also releases small amount of chlorine gas so you should do this in a big room with open windows or good ventilation.
Then we rinsed it off and then took of the electrical tape or scraped off the original paint.
And that is permanent! And a very cool addition to my key chain. Not to mention an awesome activity to take to my nieces and nephews this summer!
Then they got to the explanation of why this happens. I was following initially, but very quickly I got lost. The presenter had assumed that his audience was very familiar with the periodic table and how various elements were likely to react or not. And that was honestly an excellent assumption! The room was full of chemistry teachers (and physics teachers that remember more chemistry than I) that were nodding along and asking very detailed follow up questions that I also didn't understand.
Which only made the next part of the activity - an exploratory part where we tested if the reaction would still occur with various other chemicals - that much more intimidating. And I found myself deferring to the others about what chemicals we chose and how much water to add. I had to confirm every choice not because I wanted to include my partners, but because I doubted myself. And honestly, I wasn't really interested in the outcome. I just wanted to keep making additional dog tags.
When we were debriefing the second half of the activity I thought about asking a question to take us back a little further to my basic chem knowledge to help me bridge the gap, but it was three o'clock on Friday and I was tired! And it's not like it mattered because I don't even teach chemistry! And if later the nieces and nephews had questions I could definitely look it up and take as much or as little time as I wanted learning about the reaction. Then my phone buzzed three times in the space of two minutes and I really
really wanted to know what it said. So, I did what any good high school student would do! I grabbed my phone and excused myself to the bathroom.
On the way to the bathroom, I started laughing - only in that moment realizing how quickly I had disengaged from a lesson that I was not understanding. At how quickly my mind had moved on to my social connections and when I was going to get to leave for the day (3:30). I wanted to avoid, or at least post pone, the whole thing entirely.
In reflection, this was probably one of the most valuable experiences as it is so easy to get frustrated with a student that I know is capable and, from my perspective, just not trying or staying focused. How easy it is to be intimidated when surrounded by others that have more knowledge than you. And how exhausting it is when for every hour of every day you have to learn something new, when you aren't in control, and you don't know what is going to happen.
It is fun and exciting at times! And other times it is beyond stressful or discouraging or in some moment even boring.
But in any of these scenarios, it is always mentally
exhausting!
