The Evolution in teaching math since the 1950s:
1. Teaching Math In 1950s
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 1960s
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 1970s
A logger sells a truckload of lumber for $100.
His cost of production is $80.
Did he make a profit?
4. Teaching Math In 1980s
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 1990s
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 2009
Un hachero vende una carretada de maderapara $100. El
costo de la producciones es $80. Cuanto dinero ha hecho?