Things from my In-Box:

Last week I purchased a burger at Burger King for $1.58. The countergirl took my $2 and I was digging for my change when I pulled 8 centsfrom my pocket and gave it to her. She stood there, holding the nickeland 3 pennies, while looking at the screen on her register. I sensed herdiscomfort and tried to tell her to just give me two quarters, but shehailed the manager for help. While he tried to explain the transactionto her, she stood there and cried.

Why do I tell you this?

Because of 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 is4/5 of the price. What is his profit?Teaching Math In 1960A logger sells a truckload of lumber for $100. His cost of production is4/5 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 andinconsiderate and cares nothing for the habitat of animals or thepreservation 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 classparticipation after answering the question: How did the birds andsquirrels feel as the logger cut down their homes? (There are no wronganswers.)

Teaching Math In 2005
Un hachero vende una carretada de madera para $100. ! El costo de laproduccion es $80.