Teaching math over the years

1. Teaching Math when I was in school
A logger sells a truckload of lumber for $100. His cost of production is 4/5 of the price. What is his profit ?
2. Teaching Math In 1970s
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?
3. Teaching Math In 1980s
A logger sells a truckload of lumber for $100. His cost of production is $80. Did he make a profit ? Yes or No
4. Teaching Math In 1990s
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.
5. Teaching Math In 2000s
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, and if you feel like crying, it's ok).
6. Teaching Math In 2010
Un hachero vende una carretada de maderapara $100. El costo de la producciones es $80. Cuanto dinero ha hecho?
ANSWER: His profit was $375,000 because his logging business is just a front for his pot farm.

Seen as a comment at VA Viper blog.