When I started school we had Imperial measurements.
L s d, pounds shillings and pence. We had whole weeks devoted to teaching us to count just in money.
Think on it,
We had pounds........of 20 shillings, or eight half crowns or ten florins, 240 pennies, 40 sixpences, or 80 thrupenny bits, 480 ha'pennies or 960 farthings. Thankfully we'd gotten rid of the groat by then, there were 60 of them to the pound. Oh and a guinea was 21/-..............that's 21 shillings.
Then we had feet and inches, and yards, and rods and chains and acres and miles. 16ths, 10ths, 32nds an 64ths were common.
Pints and gallons and quarts and gills and hogsheads and tunnes.
Drams and ounces and pounds and stones and hundredweights and tons.
and they *all* had different measuring systems, different values.
Then in 1970 in came Metric and everything was done in tens

Suddenly there was time in the school curriculum for other things.........right enough the nations mental arithmatic went right out the window too
cheers,
Toddy