Classroom Connections: Trailbreakers – Dash & Dot Coding



This lesson is a very fun STEM project created to relate to the job of the Iditarod trail breakers. Unlike some of the other STEM activities I have posted, this one is much quicker. It can be completed in one (longer) class session. 


In this lesson, students work with a certain type of coding bot called Dash and Dots. They are placed into groups of no more than 4 students and challenged with coding their bot along a predetermined course. Along the way, cotton balls make up the snowdrifts that are placed along the “trail”. Other objects just as short pencils or sticks could also be used as downed trees or brush. Using a snowplow type accessory, the groups of students are tasked with clearing the path all the way to the finish and leaving a clear trail behind them. For this activity to work with 3rd and 4th grade students, the path is only going to include 90º turns, however, this could easily be adapted and changed to meet the corresponding math standards of lower or higher grade levels.

This activity begins by sharing some information and background about the jobs of the trail breakers. I reached out to Spencer Pape, lead trail breaker with Iditarod, who gave permission to share a video he put together with his team. In this (~10 minute) video, students can see how these volunteers go out ahead of the race and clear fallen trees, pack down the trail to create a firmer base for the teams to follow, build bridges over creeks and streams, and choose the path for the mushers to follow.


Using the “Blockly” app to pair the devices to the bot, students can instruct the bot to move through the course. The app is set up in a format where groups can drag directions from a set of options one side of the screen, to their code on the other side to create a workable sequential order for the bot to follow. They are given yard/meter sticks to measure distances to assist in determining the distance for their bot to move before the next direction. Students use their knowledge of angles and measurement to successfully get the bot to the finish line. 

Working collaboratively, the groups help measure the different distances, take turns entering the codes and checking the path of the bot. The bots can be coded to travel in increments of 10cm. So the students need to use the meter sticks to measure and estimate the distances needed. This activity involves lots of trial and error and resetting the “obstacles” on the path.




Teachers: View the lesson plan here: Trail Breaker Coding with Dash&Dots.docx