the evolution of math

The evolution in teaching math since the 1950s:

Teaching Math In 1950
A logger sells a truckload of lumber for $100. His cost of production is 4/5 of the price. What is his profit?

Teaching Math In 1960
A logger sells a truckload of lumber for $100. His cost of production is 4/5 of the price, or $80. What is his profit?

Teaching Math In 1970
A logger sells a truckload of lumber for $100. His cost of production is $80. Did he make a profit?

Teaching Math In 1980
A logger sells a truckload of lumber for $100. His cost of production is $80 and his profit is $20 Your assignment: Underline the number 20.

Teaching Math In 1990
A logger cuts down a beautiful forest because he is selfish and inconsiderate and cares nothing for the habitat of animals or the preservation of our woodlands. He does this so he can make a profit of $20. What do you think of this way of making a living? Topic for class participation after answering the question: How did the birds and squirrels feel as the logger cut down their homes?(There are no wrong answers.)

Teaching Math In 2005
Un hachero vende una carretada de madera para $100. El costo de la producción es $80 ......
(author unknown)