Tag Archives: LEGO NXT

LEGO WeDo Vehicle Challenge: Using WeDo kits with older students

20 Jun

The LEGO WeDo kit is designed and marketed for early elementary children. It’s so basic that even a first grader can use it, but be careful not to write this kit off as a “just-for-the-little-kids” kit too quickly.

This year, one of my favorite mini-lessons with the 7-9th grade students in the after school STEM club was this “WeDo Vehicle Challenge”:

Design a WeDo vehicle that has either 2, 3, or 4 wheels. Use only the pieces in the Wedo kit. The vehicle does not need to have steering, but it must be able to drive forward and in reverse. Innovation is encouraged. You have two class periods (1 hour each). We’ll present at the end of the second.

The kids usually take a look at the WeDo kit and presume the challenge will not be much of a challenge. Once the students get started, it isn’t long at all before they realize what makes it challenging; there is only one motor, the motor is fairly heavy relative to the parts, and that the axle sticks straight out of the center of the motor. Hmmm….

I’m guessing the challenge is probably easier for students that have prior experience working with LEGO kits and robotics; I’m not sure. (Let me know if you try it.) All my students were new to working with the NXT kits when I tried the WeDo lesson. I wanted to see how they worked when asked to think out of the box and to be creative. Following a blueprint is great for developing spatial skills and following instructions, but it doesn’t necessarily foster innovative thinking.  I found that forcing the students to work with the limited parts of the WeDo kit encouraged them to be persistent, to attempt multiple solutions, to redesign and improve, and to work together.

I’m curious if other teachers and after-school educators have tried using the WeDo kits with older students? Let me know!

Here are a few examples of our WeDo vehicle designs if you are curious… (The kids filmed the clips.)

Taking Damien Kee’s NXT “Mexican Wave Activity” for a Test Drive

16 Jun

In my last post about the Tufts LEGO Engineering Symposium, I mentioned Damien Kee‘s  presentation and included an embedded  video of his NXT “Mexican Wave” activity.

Yesterday morning, I tried the activity with a group of 21 fifth graders that had never worked with robotics before and it was a blast! It was the perfect activity for introducing the kids to the NXT robots and the NXT-G software.

We met from 9:30-12:15 and took a 15 minute snack break, so all told, we had about 2.5 hours to try to meet the following three objectives:

1) Work collaboratively in small groups to program the NXT Domabot to move from one specified location to another. Time permitting, write a program to turn the robot around and have it return to it’s starting position.

2) Gain a basic understanding of what sensors and thresholds are and find out how they apply to today’s activity.

3)Work collaboratively as a class to program all five NXT Domabots to do a wave and at least one additional choreographed movement.

Students collaborated well and worked hard and met all three objectives by lunch!

After reviewing the objectives, we warmed up with a five minute activity called “Computer Says”. (The activity is similar to Simon Says. I am the computer; students are the robots. Robots should only follow programs that start with “Computer says”) Students made three lines and faced me.

For Round 1, I said, “First we’ll learn use a motor block to run simple programs. Let’s try a few.” I then led them through a few simple commands,  “Computer says take one step forward.”  “Computer says take one step back”.

In Round 2, I said, “Next we’ll learn to use a “wait-for-sensor block and write slightly more complex programs.” I then gave a few commands like these: “Computer says wait until you hear me clap, then take one step forward. Computer says, wait until I shout loudly and then jump”

And finally for Round 3, I said, “For our third objective, we will have to collaborate to write a series of programs to get our robots to work together to create a movement wave. Let’s try to run three programs at once and see what happens. Computer says, Line 1 robots, wait until I clap then put both hands in the air and back down again. Line 2 robots, wait until I clap, then wait one second, then put both hands in the air and back down again.  Line 3 robots, wait until I clap, then wait two seconds, then then put both hands in the air and back down again.” I clapped my hands and watched as the students did a perfect mini-Mexican-wave!

The whole activity took less than 5-minutes, but it helped to build a context for what came next. Being able to refer back to the warm-up came in especially handy when we started thinking about how to program the robots to do a wave.

After our warm-up, students then learned to move their robots using a single motor block. As recommended by Damien in his presentation, I placed two lines of tape on the floor at a random distance from each other and then students worked to program their robots to start with wheels on the first line and stop with wheels on the second line. They set to work trying different motor on durations and very quickly developed an appreciation for the decimal point! If 5 rotations were too many, they tried 4, then 4.5, 4.6, 4.7…

They began to see that trial and error and persistence were important for solving this problem, and they experienced the intrinsic joy that came along with finding an exact solution to a problem.

Soon all groups had mastered the line-to-line challenge and were on to trying to figure out how to turn the robot around and bring it home. Despite my having mentioned that changing the “degree” parameter of the motor block to 180° would not turn their robot around, all the groups tried that strategy first, which led to a series of great teachable moments surrounding what “rotation” meant in the motor block. After some experimentation with the remaining parameters in the motor block, groups soon started to catch on that the steering parameter in combination with the duration setting was the ticket to that 180° turn. At least two of the five groups got the turn close to an exact 180° turn, and the remaining groups were well on their way before I cut them off and moved on to objective 2.

Once the kids had a general sense of how to move their robots and turn them, we regrouped and I introduced them to the sound sensor and to the threshold parameter.

As I usually do when explaining threshold to kids, I said, “I bet you already know what threshold means. Let me show you. Listen to my voice and when I reach your threshold between soft and loud, clap.”

I then talk very quietly and get progressively louder until they clap. I repeat and set the threshold for “really loud”. I do a few more examples of simple thresholds they understand. For example, their threshold for drinking hot liquids. I quickly made the correlation to the threshold parameter on the  sensor block. Students seemed confident they understood the wait-for-sound block and so we moved directly on to discuss how to create a wave.

To plan the wave, we created a chart on the wall that sketched what each group needed to do and then parted. We met back up about five minutes later.

On the kids’ first try, the robots took off and executed a perfect little wave. Wow! We had thirty minutes left to add a choreographed movement of our choice. We lined up 5 students to represent the five robots and planned our dance move. Groups ran off in all directions to program. Shortly after we met back up, pushed run, waited for the signal and yelled “Go” What came next was…

Terrible. Our little robots were all over the place. And so we began to learn about collaborative trouble-shooting. We came back to the line over and over again, each time it got better, but something wouldn’t be quite right.

With one minute left and groups scrambling to download their last attempts, I called them back to the line. The room was quiet. Thumbs went up to signal all programs were running. Their classroom teacher quietly counted “1-2-3” and then the kids yelled “Go!” one last time. You can see for yourself the fruits of their efforts in our video. The simple sequence of movements won’t blow your mind… but the kids’ cheers and screams of enthusiasm may brighten your day. 

Meet them where they are…

8 Feb

We’ve all heard the phrase, “Meet students where they are.” Today, I saw once again how transformative meeting a student where he or she is can be.

As I’ve mentioned in previous posts, the students who currently attend after-school robotics club, didn’t truly elect to join. They kind of got roped into it. In total there are eight students, six young men and two young women. One of the young women is especially quiet and up until today has been very shy about participating in most activities. I’ve tried to encourage her and to use my best teaching strategies to engage her, but honestly… I was beginning to think she just was not connecting to the activities and that she simply had no interest in robotics and engineering.

I ran 20 minutes late getting to club today because of a doctor’s appointment. The laptops were still down at the elementary school from Friday’s lesson with the first graders, and I didn’t have time to move them before our meeting.

I made a last-minute decision to switch up my plan for the day. (Something I don’t usually do.) Instead of working with the NXT kits and software, I took the middle school club down to the elementary lab to explore the LEGO WeDo kits.

What I observed was awesome. That quiet, non-participating  young woman I just mentioned explored and built models non-stop for the entire meeting. She then elected to stay an extra twenty-five minutes, leaving her and two others just five minutes to run to the dining hall for dinner!

She worked independently for the most part and focused on using the “Getting Started” tutorials to build the models shown. I mainly observed. As she completed each model, I engaged her in a quick conversation and asked a few guiding questions.

She was a completely different student than I had previously seen. She was 100% engaged. Check it out! Hard at work and completely in to what she’s doing! (And with no coaxing or encouraging.)

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I could see the confidence in her building right in front of me. It was amazing. I asked her if she’d like me to bring a WeDo kit to future club meetings so she could continue working with one. The answer? “Yes, please.”

The WeDo kit was perfect for introducing her to some important concepts. In just one hour, we were able to explore the movement of gears, the function of a motor, the use of a belt, and how programs are used to command the models’ movements. All she needed was to have the materials kit and the computer interface simplified. With no previous exposure to programming or model building, the NXT kit and software had been overwhelming for her, keeping her from getting involved.

When I said, “You know. The models you were building and programming today aren’t that different from the ones we’ve been working with up the road”, her face completely lit up. I think today’s experience has changed her ideas about “robotics club” and I’m excited to see where the excitement leads.

I will definitely continue to explore the benefits of using the LEGO WeDo kits with some of the older students. In addition to providing the perfect scaffolded introduction to robotics, it also brought out the playful and creative side of the students. When one student asked, “How are we supposed to build a robot if we don’t have any instructions?”, it led to a great conversation about the importance of play and trial and error.

It was a really good meeting today. There’s plenty of room for improvement, but it was really good. I can never figure out who is learning more… me or my students? I like to think we’re both learning.



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