Session 2 — Follow the Line

Opening concept: A sensor program tells Edison to keep doing something until a condition changes.

Physical activity: PL-10 (Human Line Following with Sound Cues) — this is the main activity for the first 10–12 minutes. Two helpers with different noisemakers flank the blindfolded walker and cue corrections. Let students experience the left-right oscillation, then name it: “That weaving is not a bug — it’s exactly what Edison will do. The sensor can only detect which side of the line it’s on, not how centered it is.” For new students who haven’t done PL-7, run PL-7 for 3 minutes first so they understand the basic line-following idea before adding the sound cue complexity.

Activity:

  • EdBlocks Activity 13: line-tracking sensor block
  • Students draw their own line tracks on large paper (black marker on white)
  • Program Edison to follow the line. Curves work better than sharp corners — why?
  • Challenge: who can draw a line track that breaks Edison’s line following? What causes it to fail?

Engineering connection: Finding the limits of a system is part of understanding it

Materials: Devices, USB cables, large white paper, thick black markers