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Teaching kids electronics, electricity, and logic using littleBits

Pete Brown - 05 May 2012

We homeschool our two children. Ben, is kindergarten age, Abby is pre-school age. My wife does, by far, most of the work there, including trucking them to specialized classes (art, music, gymnastics, karate, our homeschool group single day school, etc.) plus all the playdates with the other kids, and special events. Melissa even teaches several of the classes at the home school group. I generally deal with reading, since I'm in charge of story time with my son. Lately, we've split our time between him reading stories to me (I'm proud to say he's at about a 2nd grade level - you have to love personal tutoring) and me reading The Hobbit to him in preparation for the movie this Christmas. (JRR Tolkien is far wordier than I remember.)

Melissa and I also split science duties. I've brought Ben to the Banneker planetarium for a customized class arranged for our homeschool group in concert with one of the astronomy professors. I often bring Ben to SERC (Smithsonian Environmental Research Center) for their bi-weekly homeschool science class. It's nice to leave close to centers like that. Even in the 5-7 year old group, they do serious science. They worked with Microscopes to analyze feathers to explain what holds them together, learned about the scientific method, dissected something (unfortunately we missed that one), searched through oysters shells on the bay looking for shrimp, jellies, and fish, and much more.

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There are certain things that I allow the kids pretty much as much as I can afford (within reason): decent books and LEGO. The educational value of them both is apparent the minute the child starts interacting with them. Unlike TV, the computer (the kids share my old netbook), or Leapster (or Nintendo DS in the case of Ben), we don't limit the children's time on either of these. In addition, we keep a cabinet full of paper, markers, glue, paints, stickers, and other craft supplies which the kids can play with pretty much whenever they want. We like to keep things around that encourage creativity. We're not perfect by any means, but we've found that making this stuff easily accessible encourages experimentation (and large paint and glue stains on our kitchen table, and random things stuck together that you may not actually want stuck together).

I tell you all this just to give you an idea of where we are with education in my family, and how important I consider it.

Of course, none of these things are exclusive to homeschooling or to us. I'm proud of what we've done so far, but we just happen to be fortunate enough to live in an area with lots of free museums and programs geared towards home school students. Many others take advantage of these museums and programs as well, they just have to do it on the crowded weekends :).

Note also that we generally teach both children the same things, although they follow their own interests. I tend to focus on Ben in this article not because we're teaching only him electronics and science, but because his age makes these things more appropriate right now.

Electronics and programming

One thing I've been trying to find a good way to teach is electrical/electronics basics and boolean logic. Not only is this an area of interest for me, but boolean logic forms the foundation of everything you do on a computer. I want my kids to have an understanding of this to complement their ability to use the computer (yes, both kids can use a mouse or track pad, Ben can type, albeit not quickly, as well). I've also found boolean logic just about the simplest math/logic you can get. I have no idea why I wasn't exposed to it formally until college (the only math class I've ever aced, besides 10th grade Geometry).

Programming is great, but I know from my own experience, that making something happen *outside* a computer is far more impactful and memorable.

One day, I had Ben in my home office and together we stuck a resistor and an LED in a little breadboard. Ben then touched the wire leads to a 3v battery pack I had around. He thought it was awesome that he could make an LED blink (again with the blinking LED, the gateway drug of electronics <g>). I thought this was great too. However, this type of approach won't go far with a 6yo or 3yo, as it's too easy to let out the magic blue smoke. It doesn't encourage experimentation at their level.

For my two kids, I found the snap circuits kits a little too fine grained in what they do. It's much easier to connect the components compared to discrete leaded components and a breadboard, but you can still connect them incorrectly. The snaps are also bit difficult for the kids to work with, and you're really working with just an easier form factor for discrete components. Getting from empty to blinking LED is just as much work as it is with discrete components. There's still lots of value to these, however, so the set Santa brought for Christmas will simply stay around for a few years until the kids grow into it.

As much as the kids like LEGO, the engineering and programming involved in the Mindstorms kits is also well above them right now. It's marked "10+" as a recall, so we still have time :)

I'm not trying to turn my kids into computer programmers, although I think basic programming is as necessary a skill as any other for their generation. Recently, I ran across a project that started on Kickstarter, and then became its own company.

littleBits

littleBits is a company and a collection of kid-friendly hardware modules ("bits", do a mental substitution ever time I say "modules") that can be connected together to form simple electrical circuits. The starter kit comes with a number of bits including a power module, button, potentiometer, LED bar graph, and more. Shown below is the little bits kit along with seven additional modules I purchased. I ordered the kit from makershed, and the additional bits directly from littleBits.

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The overall design is Open Source Hardware, with the schematics available on github.

The connectors are custom fabricated modules which each contain three pins (or three pads) and a set of magnets. The pins are the typical Ground, Voltage, and Signal trio, with +5V as the standard high level. The polarization of the magnets prevents the modules from being connected incorrectly. Modules can be easily pulled apart, but the magnets are generally strong enough to stay connected during use (more on the connectors after I describe a few more things).

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Each module is classified as either Input, Output, Power or Wire, and color-coded by its type (input: pink, output: green, power: blue, wire (and logic gates/routing): orange). Each is also supplied with Ground, +5V and the signal through the pins on those colored connectors. Three wires may not seem like much in the way of control, but there's a thriving community doing cool things with this simple standard.

With perhaps the exception of the buzzing motor module (which has the vibrating motor attached with a few thin wires), everything is extremely robust and able to stand up to the use of kids of various ages. Both my son and daughter enjoyed playing with them.

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(the photos aren't instagrammed, they just have poor lighting)

Obviously the children each got something a little different from the process. Both enjoyed connecting them up and making something happen. Ben was able to understand the basic flow of electricity, and even a little about "AND" and "OR" logic gates. Abby enjoyed connecting all the pieces in a long chain, but also liked when she was able to test her strength against the pressure sensor (power + pressure sensor + LED bar graph == strength tester).

Ben also liked trying to connect every possible module to make something giant. However, after playing with it a third time, he started to understand a very important aspect of software and hardware design: build in small steps and test after each step. I can think of a number of professional developers who could benefit from this :)

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My son's attention span is about the same as mine: 20 minutes. After that, he tends to get pretty antsy. (This is why you generally don't find me attending sessions by other speakers, or you see me sitting in the back and bailing when the session is half over. Nothing personal!) The littleBits did keep him engaged that entire time. More importantly, in the two days I've had these, he has played with them three times. Over time, they will likely only hold his attention if we add on newer modules that do different things. Kids are all about doing, not learning. The way to get them to learn is to get them to do, and the way to get them to do, is to find something that makes it dead simple to do something right off the bat. The littleBits definitely fit the bill here.

During the third time playing with the bits, Ben really started to grasp the concept of the flow of electricity. He wanted to know what exactly it was. I found the water analogy good enough for our discussion here, especially since it helps explain the potentiometer and buttons very well. He even figured out, on his own, how the pressure sensor conceptually works.

Logic

Once you have the basics of electricity down, you can start messing with logic. I had ordered both an AND and an OR module. Each module takes two inputs and has a single output. As you would expect, both inputs must be powered for AND to produce output, and only one in the case of OR.

Here's a simple AND gate made using: Power module, branch module, button and wire modules on top, button and wire modules on the bottom, and then the AND module and an LED module on the other ends of the wires. It demonstrates a logical "AND". That is, the LED will light only if both buttons are pressed.

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The other circuits shown have been built by Ben or Abby. In this case, I built this circuit for Ben to show logic. I wouldn't necessarily expect him to come up with it on his own, although he was able to grok the concept of AND very easily from this. This is far more interactive, visual, and intuitive when compared to a truth table.

One issue with littleBits

littleBits isn't without issues, however. There's one design issue which, to me, prevents this from being the perfect learning tool. Their pin design doesn't have much compensation for poorly aligned connectors. Sprung, semi-pointed pins on one side contact flat pads on another. The pins are sprung, but the tolerance for a good connection is still pretty tight, as I found that even a slight amount of deviation from square on multiple modules can lead to connection issues for the circuit.

This very slight deviation from square, as shown here, is enough to cause those connection issues:

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Unfortunately, these connectors are rigidly connected to the boards, presumably in some sort of mass manufacturing process. As anyone who has ever developed boards with connectors knows, not all these connectors will be perpendicular to the boards once assembled. In the worst case (which happens to be in the set I have), you end up with a situation that looks like this:

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Notice how the boards sit off above the table, arched like a bridge. Right to left, there's the power module, a button module, the RGB LED module, another button module and (off picture) a regular LED module. If you press either of those two button modules, it causes the module to flatten to the table top, and disconnects the connection at the RGB module. Either I got a particularly bad batch, or this is a common issue. Like bank rounding errors famously making a crook rich, the problem compounds based on the alignment of the modules in a given circuit and the number of modules with this problem.

Generally, the impact here is really only with the button modules, and a little with the potentiometer module, and only when you have a few offending modules in a chain. It's the downward pressure required for the button that causes the problem. You can still have lots of fun without the buttons, or perhaps even put a folded bit of paper under the high module. You can also, for smaller circuits, simply pick it up and squeeze the button between your thumb and finger.

With modules this small size, the main issue isn't any warpage on the PCB itself, but the mounting of the plastic connector to the PCB base. The connectors aren't really deep enough to keep square during factory assembly.

If these modules were some inexpensive chinese thing from ebay (they're not. They're designed and assembled in the USA), I'd have expected this. However, at the prices of these modules (I'm in about $230 right now), this is an unexpected and surprising flaw. My RGB module, in particular, is really sensitive to this.

For the ones that are particularly bad, I'm going to request replacements. It may be that some slipped through production in the batch I have. Or it could simply be early production issues from a startup company trying to meet higher than expected demand. I would expect littleBits to make it right for any that are like this; they seem like an upstanding type of company.

Note that the littleBits site seems to show this issue with what I assume is a prototype kit in the slide show on the main page:

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If you tried to connect something else downstream from that LED bargraph, you'd run into alignment issues. (In this case, the LED bargraph appears to have a connector incorrectly alignment, but leaning inward instead of outward as mine do).

Caveats of the connectors aside, I still think this is a great kit to get for you and your children, and I do not hesitate to recommend it as a way to teach the things I've mentioned here. My recommendation is to simply check alignment when you get the kit, and ask for replacement of any bits that are particularly out of tolerance. Sometimes you can only tell once you connect them up a few different ways and get the compounded issue of multiple misaligned parts.

Building your own bits

Little bits has been taking ideas on their dreamBits page for some time now. The list sometimes gets overtaken by joke entries (they seem to clean those up regularly), but there are also some good ideas there. But what do you do if you want to just build the bits yourself?

littleBits has been saying for a bit (haha! I crack me up) that they will have their connectors available for sale soon. I have no idea how much they cost, but I'm pretty sure I'll pick up at least a few to try creating my own modules/bits. There are lots of interesting components you could build out, including interfaces to microcontrollers to kick things up to the next level, should you wish.

Once they release the connectors, I'll probably give a few ideas a shot, and not just to show the kids how you can create your own stuff. Why not? The grown-ups can have fun (and learn) too :)

           
posted by Pete Brown on Saturday, May 5, 2012
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3 comments for “Teaching kids electronics, electricity, and logic using littleBits”

  1. Michael McGuiresays:
    Very cool Pete! Had no idea you homeschool. We have four kids with the two older homeschooling right now and I am always looking for this kind of technical learning. Again, not to make them programmers but to give them the basics of a skill that will be increasingly important in the future.
  2. Richard Hillsays:
    Hi Pete,

    I'm just thinking ahead here - but think you may like this -: http://uk.rs-online.com/web/generalDisplay.html?id=raspberrypi&cm_mmc=UK-PPC-0212-_-02_Raspberry_PI-_-Raspberry_PI-_-Raspberry_Pi

    Its aimed at young people in the UK to get them going with electronics and programming etc!

    Hope you are well.

    Rich
  3. Petesays:
    @Richard

    Yep, thanks.

    Raspberry Pi is great. It really is for older kids and adults, of course, and they need to get their act together production-wise (hardly anyone can actually get one)

    Pete

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