For this activity, you will describe a procedure that others can follow to make a peanut butter and jelly sandwich. When listing the steps in your procedure, you should assume the person following your instructions is as "dumb" as a computer.

Specifications

A computer has no common sense with which to interpret your instructions the way you really intended them to be carried out; it is one-hundred percent literal minded. To simulate this experience, your instructions for making a peanut butter and jelly sandwich will be read and followed by the professor (i.e., computer) as literally as possible. The reader will not be allowed to provide to additional information to the professor-computer as he is working.

On the other hand, all modern programming languages provide the computer with some basic "knowledge", stuff it knows when it starts. For example, most programming languages allow you to enter algebraic expressions in the common infix format you have learned since elementary school. In other words, the computer knows how to do algebra. It is convenient to have some commands built in so that you do not have to build everything from scratch. To simulate this knowledge, there are certain things you can assume our PB&J computer knows how to:

• open any container (bread packaging, jars, drawers, etc.)
• close any container (bread packaging, jars, drawers, etc.)
• hold something (container, knife, plate, etc.)
• pick up something (knife, bread, plate, etc.)
• put something down (knife, bread, plate, etc.)
• spread a condiment (peanut butter, jelly, etc.)

But you must tell it to do them at the appropriate time! Note these are not easy tasks --- many of them are still unsolved problems in Computer Science.

Finally, our PB&J computer has the following things available on the counter to create a sandwich:

• one loaf of bread
• one jar of peanut butter
• one jar of jelly
• one knife
• one spoon
• one fork
• one plate
• one paper towel

To do Individually (10 minutes)

On a piece of paper, write the steps you think are necessary to make a peanut butter and jelly sandwich (think of it like making a precise recipe).

To do Groups (15 minutes)

Form groups of size two or three persons. You may not work alone!  You should start this group activity by introducing yourself to each member of the group.  You may also want to choose one person to write down the group's discussion on the provided transparency as you go so that it can be displayed on the classroom's overhead projector.

Compare each of your procedures and together create a single procedure for presentation to the class.