February 26, 2015
Classroom Noise Meter | 3D Printing in the Classroom
At the beginning of the year my school district adopted a new program for classroom management. I’m not sure if we have ever had a district-wide program for that, but we do now. A new program means new training, and we had a few meetings about our new program. Here’s a link to a description of the program if you are interested.
One of the features of the program is using and teaching a numbering system to monitor the noise level of the students. A zero means no talking, one means whisper, 2 means partner talk… you probably get the idea. Anyway, while they were describing this all I could think of was the movie “War Games” and how they kept changing the DEFCON (defense readiness condition) level. Here is a clip from the movie to put in perspective what was going through my mind.
I figured my class would look just like that and I want to be able to say “Go to DEFCON 2.” when it’s appropriate. Of course, that would mean I would need a cool box with numbers on it that would light up. And a new classroom project with 3D printing was born.
I rounded up a few students, shared my idea with them and turned them loose. In no time, they had painted a box we had found, cut out rectangles for a face plate with windows, glued colored cellophane to the windows, and glued on numbers.
It already looked like a DEFCON indicator. Now we just needed to figure out how to attach the face plate, and figure out the lighting.
Attaching the face plate with the windows turned out to be easy. We just cut the center out of left over baby food jar lids that are left over from another project we have done . Then we glued the metal pieces to the corners of the box, and attached magnets to the corners of the face plate. Now we can remove the face plate to work on the circuitry inside the box.
The lighting turned out to be more challenging than I thought. Mostly because the LEDs that I have are not very bright. One little LED inside the box really did not do much, and the light beam is so concentrated that it only lit up one little bead of light on the cellophane.
At this point I had a student’s father volunteering in the room and I let him work with the group to come up with a solution. He suggested using something to diffuse the light and spread it out more in addition to using multiple LEDs pointed in different directions.
The kids liked the idea, they also glued tin foil inside the box to help reflect as much light out as possible. They found a translucent trash bag that did a decent job of diffusing the light, and it looked like we had a good solution to the dim LEDs.
Now it was time to do some designing on the computer and some 3D printing. We needed a box to house the switches. Similar to last year’s Mission Circuits switch box. We also needed a way to mount the LEDs so they would point the direction we wanted them to.
The students went to work and after much trial and error they had a switch box that looked like it would work. We loaded the file onto our 3D printer and realized it was too big to fit on the printers bed. Back to the drawing the board they went.
The second version fit perfectly and we started printing it. I don’t know if I am the only person that has this problem, but I have no luck with printing things that are flat and take up a lot of space on the print bed. They always seem to peel up at the corners and ruin the print job. It took me several tries to get one to print correctly, but we did it.
The box came out just right. I was so impressed with how precise the measurements were. The switches fit snugly into the holes, and we are ready for the next phase of this project, the circuitry.
While the switch box was printing our lead designer quickly made up some mounts for the LEDs. They are a simple “L” shape designs with a hole in one of the sides for the LED to stick out of. I was really impressed with how quickly my student was able to create the computer design of the mounts. The 3D prints came out just right. He was so precise with the measurements of the holes that the LEDs slid in just right.
It just so happens that we are in the midst of our electricity unit in science. Giving these students a project like this really takes their learning to another degree. It gives them a reason to try and understand what they read in their textbooks and provides more context when they work on their own experiments. They have a purpose for their learning, and we have an immediate use in the classroom for that knowledge.
The academic language is rich as well. We have conversations using words like series and parallel circuits, components, insulators, conductors, positive and negative leads, etc… The students have higher level conversations correctly using the terminology.
The circuitry for this box is much more complex than a simple circuit they can make at their desks yet they are excited for the challenge. They know it is going to be a useful addition to the classroom. I over heard one of the girls say, “This is so cool! I’m totally putting this up in my room at the end of the year!”. She might have to fight me for it, but I’m glad she is so invested in it.
I’m excited to see this thing come together. The students are applying many of the skills they have been learning this year and gaining new ones along the way. I have another idea for what to do next with this thing, but you’ll have to tune back in for that one.