An old Girl Guide tie, a robot and The Brownie Tie Robot

Brownie Tie Robot: STEM and the Key to Brownies

I recently started as a Brownie leader (Dragon Owl, I hit the jackpot letting the girls pick my name). So I’m adding a new feature to this blog where I share science related meeting activities. Most of these will obviously fit with the Key to STEM, but science can fit in with a lot of Keys so there’ll be variety.

It’s science week, so we wanted to have a really science based meeting this week. But since it was only our third meeting, we’re still working away at the Key to Brownies. Especially since we’re a brand new unit and only two of our sixteen girls have been Brownies in the past.

This activity introduces some basic computer programming ideas while practicing how to tie their Brownie tie.

An old Girl Guide tie, a robot and The Brownie Tie Robot

No sense keeping science in the Key to STEM


I’ve basically made it my goal to get the Brownies familiar with as many women in STEM as I possibly can. So I opened this activity by asking them if they knew that the first computer programmer was a woman. A few of them had heard that but they couldn’t name her. I told them a little bit about Ada Lovelace and why she was important before diving into robots.

The key to this idea is that while computers can do calculations very fast, they’re actually not very smart. Specifically, a computer will do exactly what its code tells it to do. (We got a bit side tracked by viruses making a computer not doing what they ask and how that’s other code changing the instructions)

The Brownie Tie Robot

For this activity, get the girls to pair up. Each pair needs to have one Brownie tie so this works even if not everyone has their uniform yet. I brought my old Pathfinder and Ranger ties in just in case we had a shortage.

Old style Ranger tie lying on the floor

I remembered to be prepared!

One girl is a Brownie tie robot and the other girl takes on the role of the programmer giving her instructions on how to tie the tie. The programmer has to take the robot through step by step. If the programmer’s instructions aren’t specific enough, the robot won’t be able to do it quite right.

Once the robot manages to get her tie on, the girls should swap roles.


After everyone had a chance to try both jobs, I brought the girls back into a circle so we could talk about what they learned. I asked the girls if anyone’s robot did anything crazy and we got a lot of good answers.

A Ranger tie folded in thirds

Exactly the hijinks I was hoping for

  • One robot kept putting the tie tag side down until the programmer realized she needed to tell her to put it the other way. This is like declaring the initial values of variables in programming.
  • One folded the tie into thirds until the programmer realized that she needed to specify that it should be three small folds. Making sure you include all the right measurements and units.
  • One robot’s tie wound up way too tight because her programmer didn’t say when to stop pulling the ends. Specifying your end conditions!

The girls playing the robots had a lot of fun with the idea that they should be following the instructions very literally and the programmers learned a lot about how to cope with that.