Pulling this one from my drafts folder to share …. not certain how long ago this was but the concept was sound (and fun) so here ya go.
I drew several lines on a sheet of paper and then marked the increments of various measurements on each one. (1 inch, 1/2 inch etc.) Brother’s task was to roll out a snake of playdough the length of the line then use a butter knife to cut it into the correct increment.
We then compared the cut pieces with a ruler. This was mainly intended to be a motor skill exercise with a bit of math thrown in for fun but the visual must have really made it click for Brother because when we got to the ruler part he began explaining to me how many half inches were in an inch and how a quarter inch was double again. Gotta remember this one.