Over two lessons, Year 8 pairs build a micro:bit pacer that also carries a model of the heart. In MakeCode, pairs program it to beep at a step rate chosen with the A and B buttons, from 15 to 40 steps a minute, and to show a heart icon that beats at a model heart rate their program calculates: it starts at a resting value, climbs towards a target set by the step rate while the test runs, and falls back when the stepper presses both buttons to stop. Most first versions jump straight to the target and drop straight back, so pairs test on the simulator and write rules for how quickly the rate rises and recovers. In the second lesson each student does one-minute step tests at two rates with a pair's pacer, counts their own pulse straight after and again a minute later, and compares it privately with what the model heart showed; nothing is written on shared sheets or collected. Pairs then rewrite their rules, and the class discusses, with no pupil's numbers shared, which features of the model matched real bodies and which it still leaves out, such as fitness.
Tools: MakeCode, micro:bit Nine ideas for your own version in Generate
This page is one of a growing set of PICRAT examples by cell, subject and grade. Page maintained by Andy Perryer.