How Computers Work

Overview

The purpose of this activity is to give the students a basic sense of how computers work by having them act out a simple computer simulation.

Each student takes on the role of a different part of a simplified computer and they work in groups to run a simple program. The end result of this program is to draw a picture on a simulated computer display.

It is designed for groups of 3 students, although it can be adapted to work as an individual activity or with groups of 2-4.

Prerequisites

Ability to perform simple addition and plot (x, y) coordinates on a grid.

This activity is designed for students in grades K-8.

Description

In this simulation of a (greatly simplified) computer, we consider a computer as being comprised of 3 major components:

CPU (Central Processing Unit)
This is the part that executes the program and tells the other components what they need to do.
ALU/Memory (Arithmetic/Logic Unit & Memory)
The ALU is the part of the computer that performs all the math and logic operations. The Memory keeps track of information so that it can be recalled later.
Display
The Display is the part that shows the results to the person using the computer.

We assign a student to each of these components and give them a simple program to run. The student acting as the CPU processes each instruction in order and tells the ALU/Memory and the Display what to do.

While the program is being run, the Display should hide the image so that the CPU and the ALU/Memory have no idea what it being drawn on the screen.

Once the program is done, the Display shows the result to the other members of the group.

Documents

Download all these PDFs in a single .zip file: how_computers_work.zip

	Display (PDF, SVG) The student acting as the Display should use this worksheet to record what is being shown on the computer's display.
	ALU/Memory (PDF, SVG) The student acting as the ALU/Memory should use this worksheet to keep track of the current x and y values.
	CPU The student acting as the CPU takes one of the following programs and runs it by telling the ALU and the Display what they need to do. Program #1 (PDF, SVG) Answer Key (PDF, SVG) Program #2 (PDF, SVG) Answer Key (PDF, SVG)
	Instructor Info (PDF, ODT) Description and additional information for this activity.