From an American website:

Arithmetic Tests Through the Decades

1960's
A logger cuts and sells a truckload of lumber for $100. His cost of
production is four-fifths of that amount, and the taxes on the sale
are 7%. What is his net profit?"

1970's (new math)
A logger exchanges a set L of lumber for a set M of money. The
cardinality of M is 100. The set C of production costs contains 20
fewer items than does M. What is the cardinality of the set P of
profits?

1980's
A logger sells a truckload of lumber for $100. His cost is $80 so his
profit is $20. Circle the number 20.

1990's
A redneck logger massacres a beautiful stand of trees to make a profit
of $20. Write an essay explaining how you feel about this ruthless
capitalistic exploitation. Try to explain how the birds and the
squirrels feel.

Jack