Designing Lego WeDo Insects

Engineering Design Cycle

At our school we use the Engineering Design Cycle to go through STEAM units from Pre-K through to 12th Grade. It has kept our vocabulary and process consistent through the school, while at the same time allowing students to develop and hone their skills and thinking year after year. This cycle lends itself very well to many things that I do in Technology with the students, most especially when integrating robotics.

Insect Mania!

We all KNOW when second grade has hit this unit because of the hum of crickets that echo out of all six classrooms! They study insects closely during this science unit and will host quite a few of these little guys such as, meal worms, crickets, darkling beetles and caterpillars which later turn into butterflies.

In an effort to expose the second graders to more robotics and design, I planned three-lesson series where they would get to:

1. Explore and inquire into the Lego WeDo pieces

2. Program their Lego insect to move, make a sound and have a fact about their insect appear on the screen

3. Design their insect to look like an insect as much as possible without compromising the movement

Lesson 1: Explore, Inquire, and Understand

I began this lesson by having students do a gallery walk of four Lego WeDo animals that we had already built and programmed, all they had to do was click play. I allowed them to pick up the animals, look at the gears move and how they were connected to motor etc. Once this was done, I left the animals at the front of the room in case any students wanted to come back to reference them.

I then gave the students free reign to the Lego WeDo kits to attempt to build an insect of their choice with their partner. This was like a little assessment for me as well. I got to see which students could figure out how gears, motors, and axles could all come together to make something move. It also really let those students who had exposure to Lego Robotics already shine through. Needless to say, all the students were chatty, moving around the classroom asking for peices from other groups and learning from each other. Some groups even attempted to build in a sensor to their insect! Here are a few examples of what happend after the end of a one hour free exploration lesson:

Some students did manage to build something that we could plug into the computers and test at the end of the lesson, but majority were still trying to figure out gears and attachments. As you can see in the pictures, they weren't quite ready for testing and were still working things out!

Designing Bases

In light of this, I decided that I should try to build a couple bases that students could choose to work off of, OR if they had more expertise, could continue designing their own insect. This was pretty fun for me as I had to try to figure out myself, how to make mechanisms that would move forward and backwards, walk with alternating legs, jump, or flap its wings. I tried to keep them as simple as possible so that it gave plenty of room for student design. Here's what I came up with:

Lesson 2: Building and Programming

At the start of the second lesson, I introduced the four bases that I had made and told them they could choose to make one of these or if they thought they had their own design, they could go with it. Majority chose to use one of my bases except one group. They followed photo instructions that we made in order to build these bases and then we plugged it in and began to program. I told them that they must complete their program before beginning to further design their insect because if they put all of their effort into their design but then get their program wrong, it could break apart.

As I mentioned earlier, the students had three tasks, the first was required, the other two were extensions:

1. Make your insect move the way you want it to

2. Add a sound to your program

3. Make one or more facts about your insect appear on the screen

Some classes had every group get to the third stage in programing whereas some had groups that needed the whole class to figure out just the first part. All groups were successful in making their insect move.

Lesson 3: Designing and Improving

This was the lesson where students had the chance to build onto the bases and design their insects. They had to think carefully about placement of blocks and test their insect's movement throughout the design since putting weight in different places could affect the movement, which would later either lead to a redesigning of their actual robot OR a redesign of their program, such as increasing the motor's power to counteract the added weight.

Students had their classroom iPads during this lesson to take short video clips and photos of their process and final product which we will later use to create an iMovie reflection.

Here are some examples of insects in action: