WEMS Elementary Technology

Wray, 2015-06-04, Classes

binary, edtech, leds, transistors

WEMS Elementary Technology

I have had a really great time teaching Technology to the WEMS Elementary students! They have been such a terrific and patient class this year as we reviewed things as complex as Binary Logic gates, the binary number system, and even the hexadecimal number system. I truly enjoy instructing in the Montessori environment as they are so open to new concepts and can help me relate them to their other subjects. And the older students are able to help the younger students in a way that reinforces everyone's understanding. I especially appreciate their patience because we steered away from the afternoon iPad sessions and stuck to a more traditional lecture/show-and-tell approach -- they did some iPad technology work on their own.

Due to the recurring request by the students for me to bring them transistors, they now each have their very own (PNP) transistor and an LED! Again, I am so pleased with their enthusiasm and now understanding of how transistors (used to implement switching/digital logic) are the basic building blocks for the digital devices we all own and carry around today.

And for those students who actually want to build something with their transistor and LED, you can go to adafruit and amazon (specific links to items coming) to order a few additional items to build a simple switching circuit and even a NOT gate (ask your child to explain a not gate -- hopefully they'll remember what a truth table is and show you the truth table for AND, OR, and NOT). To get started with their transistor and LED, they should probably get:

Feel free to order more switches, transistors and leds. You may want to see if the remaining Richmond Radio Shack stores still have some electronics project starter kits which include many of these things in one nice bundle.

You can then build this simple circuit whereby pressing the button turns on the transistor which turns on the "main" circuit to turn on the LED. Note the position of the transistor -- the flat side is facing down in the pictures (which lines the three leads to the transistor to be in the order of emitter, base, and collector). Your child may remember earlier in the year when we had several of them pretend to be a transistor and we had one student providing power, one student controlling, and another student as the LED -- the controlling student was "wired" to the base.

Simple switching circuit -- off Simple switching circuit -- off Simple switching circuit -- on

Then, your child should enjoy this simple wiring change that allows the transistor to stop the "main" circuit. That is, pressing the button will turn off the LED -- essentially creating the NOT logic. The light is on unless the button is pressed.

Not gate -- off Not gate -- off Not gate -- on

Please feel free to comment here or send me an email wray(at)techemstudios.com .