Sunday, September 27, 2009

The NXT Brick - Unplugged

The NXT 2.0 software includes new firmware (see previous post) that lets you create simple programs directly on your NXT brick - no computer required. I've prepared an exhaustive tutorial for your enjoyment.

Monday, September 21, 2009

Hardware, Software, and Firmware

Apologies if this post sounds like an advertisement for LEGO products...

To get set up for the LEGO Engineering program, the school bought the LEGO Education NXT kits - the standard 9797 set. We also bought a site license for the NXT Software 2.0, which (new in 2.0) includes "data logging" capabilities. That means that you can take measurements (using any of the sensors) over a period of time and record the data. You can then graph the data - either on the NXT or on a computer. I'm really looking forward to using these capabilities. Note that there's no difference in the NXT brick - it's just the software.

Firmware Version 1.28
With the NXT 2.0 software comes a firmware update, to version 1.26. But... don't install it. I heard from one of the attendees at our LEGO Engineering Conference that his NXT sometimes froze when doing line-following. The good news is that there's a firmware update (1.28) which he said fixed the problem. I highly recommend it. It has a very, very cool feature: you can do simple programming directly on the NXT brick - no computer required. I'll try to make a post about that feature.

Based on one person's experience, the 1.28 firmware seems to be compatible with the 1.0 NXT software - which is great! However, if you decide to try it, make sure that you have the older 1.05 firmware handy in case you need to revert - just in case.

One annoyance is that the firmware comes in a ".rar" file, an archive format like ".zip" or ".sit". I had never heard of it, which is saying something. On Windows, I'm told that WinZip, which you may already have, can unpack the file. If you don't have WinZip, the free utility 7-Zip will do it. On the Macintosh, a program called The Unarchiver will do the trick.

Charging Multiple NXT Bricks
I lied. The school didn't buy the standard 9797 kits. Those come with the rechargable battery (good) and a wall-wart style battery charger (bad). I hate wall warts. I especially hate the thought of 16 of them plugged into 5 or 6 power strips, plugged into another power strip. So, I had the school buy the W991501 8-Pack plus light sensor - you get a second light sensor and no battery charger.

So, how do we charge the batteries? Long ago, I started out as an electrical engineer and I still like to tinker. I built 3 "multi-chargers" that can each charge 5 NXT bricks. They take up way less space, have longer cords, and less wire tangling.

Friday, September 18, 2009

Motors are hard to attach, let's play with the wheels!

Today was the first day of the second week, which was "build a sturdy car". We showed them the sample car from the curriculum, which was - intentionally - pretty lame, but the net result was that most of the kids just completely froze on the problem. After all, look at them:

Most of the obvious ways have bits getting in the way or end up with the wheels pointing the wrong direction. This was my moment of quiet panic. So, we showed them the basic double-joiner elements:

and they got the idea that you could use those to directly attach the motors to the sides of the NXT brick. So, most of the cars were wide, like this:

But there were several interesting designs:

Nevertheless, too many kids didn't know where to start and endured a lot of frustration. We still want them to wrestle with the design process, but some of them clearly needed some hints. So, I found this great resource from the LEGO Engineering site: Constructopedia 2.1 | Ways to Attach NXT Motors (PDF, 29 pages) It shows 8 different ways with detailed building instructions. Since we don't want to take away all of the "fun", I think that we might just provide copies of the overview picture for each design - to be used as needed. (Oh, and even if we give them a solution for motor attachment, they still have to figure out the "front" wheels.)

End-of-week update:
Providing the motor attachment hints really helped. Most of them (that needed the help) were able to get by with just seeing the overview picture, not the detailed building instructions. Here are some of the other cars:

Wednesday, September 16, 2009

Parents' Night in the Lego Engineering Classroom

You remember parents' night at school, right? Parents get to go to your classrooms, sit in your desks, listen to your teacher talk about what you'll be doing all year. The Lego Engineering classroom on Wednesday night was a bit different....

Children who had temporarily escaped their parents were clustered around desks taking apart and putting together parts of the partially-assembled cars from Week 2. Parents would occasionally walk in looking lost (as we were not giving any formal presentations...too boring), and given that I speak Spanish and many of the children come from Spanish-speaking households, I would rein them in by asking them if their kids had told them about the class. The lost look would disappear, and they would tell me how much their children had been talking about this class and how the older siblings were jealous that it hadn't been offered when they were in 3rd or 4th grades.

I told them some of the basic principles that their children would be learning about, e.g., how to solve problems by trying things out rather than reading text books and answering questions. One mother was fascinated because her child has been having trouble paying attention in school, and for the first time has become fully engaged in a class (and of course is begging for an NXT kit of his own). She sees the connection between this class and the basic skills he needs to work on, like reading: if he wants to pursue Lego Engineering as a hobby, in the absence of a teacher or volunteer, he'll need to read instructions, find information on the web about how others have solved problems, etc.). Another family had two younger daughters not yet old enough for the class, and simply wanted to find out what all the excitement was about. They were genuinely grateful to the Google volunteers for their time and effort, and recognized the value of exposing children to alternate forms of learning that they may not have access to at home.

Saturday, September 12, 2009

More Observations regarding STOMP

[Originally posted by Joe]
  • Kids love wheels. Most of the kids started on the chair exercise by figuring out how to attach wheels to a flat surface. I'm not sure why. I tried to point out that the goal of the project was to build a chair, and that the wheels could come later.
  • I also note that design sessions at Google often start with the wheels, even though the goal is a chair!
  • The handouts we had for the initial activity (building an arch) were hard to read. The graphics were so dark that a key part was nearly invisible.
  • We didn't spend enough time teaching kids how to put together the "new style" Lego parts. Most of them tried to attach parts the old way (with stud and hole) rather than the new way (beam and connector).
  • Random assignment of kids to teams mostly worked, but we had one team that lagged. One of the boys had difficulty understanding the assignment, and some problems with manual dexterity. The other boy was either bored or unmotivated, and didn't spend much time doing anything other than fooling with parts and singing to himself.
  • My experience justified my prior belief that we don't pay teachers even half of what they're worth.

Wednesday, September 9, 2009

Our first day in the classroom

The first activity was "A Chair for Mr. Bear", where the kids had to build a chair out of LEGO elements that would hold a small stuffed bear and meet a couple of requirements: sturdy enough to survive a drop to the floor and stable enough to not fall over if you gave it a little shove. The main purpose is to introduce the kids to the parts they'll be using and to teach them a bit about how to build strong structures. (Remember the bridge that didn't fall down?)

A little bit about the classroom...

We have a separate group of volunteers assigned to each of the three fifth-grade classes. The classes have about 30 kids each, with the kids working in pairs. The LEGO Engineering sessions are 90 minutes long, right at the end of the school day. Working in pairs seems to be universally regarded as the right choice for this activity:
  • There's no way to have 30 LEGO kits and enough room to work.
  • Teamwork skills are essential all through life - we may as well start now.
  • Three-person groups do not work at all - one kid will always be sidelined.
Note that this is not a special choice program: all of the kids in the class participate. Pairs are randomly assigned by drawing labeled craft sticks (a.k.a., tongue depressors) out of a "sorting hat" at the beginning of each session.

Back to building chairs...

One thing that I enjoyed pointing out is that the first two engineering steps (identify the need; research the need) were being done for them: We're telling them that the bears have sore feet and that the solution is to build chairs for them. I also point out that a good engineer who did proper research would probably have come to the conclusion that several sacks of leaves might be a better solution.

We showed the kids several deliberately-flawed chairs and let them go at it. On the first day, we realized that most of the kids had no idea what the different LEGO Technic parts did or how they could connect together. On later days, we had them build some simple structures (PDF, 3 pages) as a warm-up exercise. I'm not really sure that that helped, because we got a lot more "successful" chairs on that first day. Go figure.

Once a couple of pairs had chairs built, we had them come up and present their designs. They were not expecting this! However, they were all excited to present their (emphasis on ownership, here) chairs and describe the cool features. They really liked having us take pictures of their chairs. I built a light tent to take the pictures, and am thrilled at how well it worked.

Here are a few bear chairs.

Note: variations in bear-like characteristics should be expected and are a natural consequence of the bears' origins.

What do engineers do?

The first week's activity starts with a gentle introduction to the engineering process, which the Tufts curriculum describes as consisting of 8 parts:
  1. Identify the Need/Problem
  2. Research the Need/Problem
  3. Develop Possible Solution(s)
  4. Select the Best Possible Solution(s)
  5. Construct a Prototype
  6. Test and Evaluate the Solution(s)
  7. Communicate the Solution(s)
  8. Redesign
Current events provided us with an excellent illustration of an engineer's work: The weekend before, a truck carrying a large backhoe was 6 inches (15 cm) higher than the Mathilda Ave. overpass at Highway 101. Large chunks of concrete were ripped out of the bridge (fortunately, not causing any injuries) causing the bridge to be closed for a few days while they figured out how bad the damage was. This gave us some great talking points about engineering:
  • Why didn't the bridge fall down? [Engineers designed it to be strong against heavy loads, earthquakes, and damage like this.]
  • Who did they call in to see whether the bridge could safely carry traffic and be re-opened? [Engineers, of course.]

Tuesday, September 8, 2009

Introductory message...

Google engineers teaching fifth-grader students using LEGO toys?

Ever wonder what Google engineers do for their 20% projects? Well, this one isn't typical...

Back in December of 2008, we invited some folks from Tufts University's Center for Engineering Education and Outreach (CEEO) to talk about "LEGO Engineering, from Kindergarten to Graduate School" (video). They described how LEGO building toys - especially the NXT - can be used to enhance science, technology, engineering and math (STEM) education at all levels. Not only that, but Tufts have a program which they call STOMP (yes, it's an acronym) that brings LEGO Engineering into the classroom. They provide training, curriculum, and a community.

I've wanted to find some way to bring these sorts of educational tools to under-represented communities. I fit in well at Google - we are seriously interested in increasing diversity in engineering-related fields - we need our future engineers to reflect the diversity of the people using our products. Interested? Totally!

The project is described in greater detail here, but the short summary is that small teams of Googlers will spend 90 minutes, once a week, teaching LEGO Engineering at Bishop Elementary School in Sunnyvale (near Highway 101 and Mathilda). We're using the curriculum provided by Tufts, modified to fit our experiences.

We started off, on August 24, by holding a LEGO Engineering Conference to get the teachers and volunteers familiar with the program. The next step is to for the volunteers to actually start teaching in the classroom. That will be another blog post. And another. And another...