What Unique Microscopy Samples Can Engage Kids in STEM Learning?

[chrisr]

Hi. I'm a retired several-sciences guy, a STEM Ambassador encouraging kids to look at science, hopefully fostering interest.
I'm also interested in microscopy.
I/we are looking for ideas for small items which demonstrate interesting/educational things, for kids to look at through microscopes. I'm trying to get away from traditional pond life and random tissue samples.
This is for age 11-18 students. Item size around an inch, down to hair diameter size.
Schools would get some photos/posters to put up, then I/we turn up with a trunk of scopes (schools would have some too) and a load of mounted specimens to look at. I can make (focus-stacked) images for annotated descriptions. I can prepare section specimens of most things, and mount them in clear acrylic blocks.

Any branch of science -
examples:
all the sensors in a cell phone - accelerometer, compass, camera, microphone, vibrator, speaker,
LEDs and light sensors, section of the screen, & RGB,.
Gas sensors, pH probe, QI filament lamp showing recrystallization in the halogen cycle, heads on a hard drive, a sectioned battery, composite materials, ball pen tip, stomata on a leaf, scales on a butterfly wing, a stent (as in blood vessel), tip of a hypodermic needle,
credit card cut through showing the aerial and processor. Oh and bullets - new empty , and used, .22 shells.

The microscopy can use fluorescence or polarized light.
Anything else? If it ties up with regular school curriculum but is something other than they'd routinely look at (like mitosis in onions) so much the better. Medical is always interesting.

Perhaps you've seen pictures of things, which you could suggest?
Anything you'd like to see illustrated?

 

[.Scott]

First thing that comes to mind is bugs - mosquitoes, grasshoppers, etc.
Different fabrics.
Their own fingers and finger nails.
Rocks, dirt, sand, asphalt

 

[chrisr]

Thanks for the reply Scott!
I should have emphasized that I'm looking for things which relate strongly to the schools' curriculum. The reason is that schools (teachers) are up to their eyeballs in teaching the exam stuff. It's really quite hard to get them to look at other things. So, fundamental principles, particularly.

Insects is a great idea, but sadly they don't spend much time at all on insects. There IS, so thanks for reminding me, attention to respiration generally, so spiracles on the sides of insects, caterpillars etc are relevant.
The butterfly scales directly show diffraction of light, which is what gives the color. Fly wings could show interference - except that most don't!

General pond critters for example, though fascinating for microscopists, hardly get a mention in school. It's tough to get past the teachers!

Things like phone touch screens aren't on the curriculum yet either, but with some effort, can be explained in a relevant way, and they are very familiar technology. Solar panels too maybe.

Asphalt - not sure - but it lead me to think of concrete - where a chemical reaction with cement sticks the mixture together - thanks that's going in!

Anyone think of a structure where ion transport is evident? Smoke alarms...?

 

[Stephen Tashi]

I should have emphasized that I'm looking for things which relate strongly to the schools' curriculum.

You should reveal the school's curriculum in detail.

 

[chrisr]

Well, as I say it's ages 11-18 so you'd probably guess right. I guess all the readers of this forum have been there ;).

It was harder to find a USA list than a British list, but Wikipedia has one:
https://en.wikipedia.org/wiki/List_of_physics_concepts_in_primary_and_secondary_education_curricula
https://www.genome.gov/12011721/curriculum-topics-covered-in-high-school-science-courses/
https://www.gov.uk/government/publi...iculum-in-england-science-programmes-of-study
https://assets.publishing.service.g...ile/593849/Science_AS_and_level_formatted.pdf

Many of the sensors in cell phones are interesting when sliced through - G meters, sounders, microphones, the vibrator, the multi-frequency aerial.
Then there's the indium-containing touch screen, LiPo batteries.Power dissipation in the LED, and its differential coefficients of expansion between the plastic and the metal.
Compare the LED with a tungsten-halogen bulb, thermal considerations, with the addition of the re-crystallization of the filament as the tungsten condenses back on it in the "halogen cycle".
Sections though smoke alarm sensors (radioactive bits removed), gas sensor probes, pH sensor probe.
A sectioned bullet would entertain some boys and some fluorescent make-up with shimmering diffractive flakes, some girls.
If I can wrangle a gecko I could try to show the lamellae on its feet which stick to the ceiling using Van der Waal's forces, but they are rather small.
Car bulb:
http://janrik.net/MiscSubj/2009/PuzzleC20090225/Crop1.jpg

Ideas anyone?