Car 1 This car gets regular oil changes and maintenance checks. All essential fluids are checked and replaced regularly, as are the tires and break pads.
Car 2 This car's oil was changed when the light came on. It's been in for maintenance twice, once at 30K miles and once at 100K miles. The car's tiers were replaced when it slid in a snowstorm.
Much like regular maintenance checks, formative assessment is a technique we can use to "diagnose" student understanding early, so that we may adjust often and improve learning outcomes.