The teacher shows a box of books, a newton meter and a set of round dowels, and asks how much force it will take to pull the box across the table with and without the dowels underneath as rollers. Each pair posts a predicted reading for both pulls and a reason to a Padlet with three columns: more force with rollers, the same, and less force with rollers. The teacher reads out the reasons in each column, then runs both pulls with a pupil reading the meter aloud. Pairs finish by adding a comment to their own post saying what the readings showed and which part of their reason held up, and the teacher picks out any that mention friction between surfaces.
This page is one of a growing set of PICRAT examples by cell, subject and grade. Page maintained by Andy Perryer.