I hadn't seen this one in a while, and there have been a couple of additions since it last graced my inbox, so I thought it was worth sharing with the world again:

Last week I purchased a burger at Burger King for $1.58. The counter girl
took my $2 and I was digging for my changed when I pulled 8 cents from my
pocket and gave it to her. She stood there, holding the nickel and 3
pennies, while looking at the screen on her register.
I sensed her discomfort and tried to tell her to just give me two quarters,
but she hailed the manager for help.

While he tried to explain the transaction to her, she stood there and cried.

Why do I tell you this? Please read more about the "history of teaching
math":

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 exchanges a set "L" of lumber for a set of "M" of money. The
cardinality of set "M" is 100. Each element is worth one dollar. Make 100
dots representing the elements of the set "M." The set "C," the cost of
production, contains 20 fewer points than set "M." Represent the set "C" as
a subset of set "M." Answer this question: What is the cardinality of the
set "P" of profits?

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
By cutting down beautiful forest trees, the logger makes $20. What do you
think of this way of making a living? Topic for class participation after
answering the question: How did the forest birds and squirrels feel as the
logger cut down the trees. (There are no wrong answers)

Teaching Math In 2000
A logger sells a truckload of lumber for $100. His cost of production is
$120. How does Arthur Anderson determine that his profit margin is $60?

Teaching Math In 2005
El hachero vende un camion carga por $100. La cuesta de production...