Reforming the teaching system is a subject of constant controversy. A group of high-level highly-qualified teachers studied this problem, and specially a question that was worrying the large majority of future students (well..., er... their parents): The evolution of a mathematical problem. You can feel the problem through this comparison: Teaching in the 60's: A farmer sells a bag of potatoes for $100. Production costs used 4/5 of the sales price. What was his profit? Traditional teaching in the 70's: A farmer sells a bag of potatoes for $100. Production costs used 4/5 of sales price, that is, $80. How much was his profit? Modern teaching in the 70's: A farmer exchanges a set "P" of potatoes for a set "M" of money. The order of the set "M" is 100 and each element is worth $1. Make a draw of 100 dots representing the elements of the set "M". The set "C" of the production costs has 20 dots less than the set "M", so answer now the next question: What is the order of the set "B" of profits? (draw its elements in red). New teaching system of the 80's: A farmer sells a bag of potatoes for $100. Since the production costs were $80, the profit was $20. Now, underline the words "potatoes" and discuss it with your class neighbour. Reformed system of the 80's A privileaged Kapitalist steels injustly $20 over a beg of patatous analize the text and find out gramatik. ortografy and ponctuation erros and say something about dis process of getting reach. Computer Aided Instruction in the 90's: A sales engineer of an agriculture facility consults the Agro-BBS which he accesses through a PS/2 running OS/2 (50Mb hard disk, 4Mb 80 ns RAM, 25 MHz 80386) to find out the current day's price of potatoes. He introduces the value in his spreadsheet program, analyses linear regression tendencies in his FARMMANAGER expert system, and after seeing the results in his new VGA-compatible multisync monitor, and saving the results in the disk (not forgeting to backup it) he outputs the result to a color laser printer (using Post Script). Make a drawing with your mouse of the 3-D integrated contour of a bag of potatoes. Next, log in the Agro-BBS and follow the instructions of the menu. Teaching in 2000's What's a farmer?