THE NOTION OF INTELLIGENT MACHINES FOR TEACHING PURPOSES can be traced back to 1926 when Sidney L. Pressey built a machine with multiple choice questions and answers. This machine delivered questions and provided immediate feedback to the user. Educational Psychologists have since reported that carefully designed individualized tutoring produces the best learning for most people.

ITS is a system that provides individualized tutoring or instruction. Each ITS must have these three components:

• knowledge of the domain
• knowledge of the learner
• knowledge of teacher strategies

The domain refers to the topic or curriculum being taught. The learner refers to the student or the user of the ITS. The teacher strategies refers to the methods of instruction and how the material shall be presented.

This basic outline of requirements has been around since 1973 when it was introduced by Derek H. Sleeman and J.R. Hartley. (Hartley & Sleeman, 1973). The goal for every ITS is to communicate its embedded knowledge effectively.

A student learns from an ITS by solving problems. The system selects a problem and compares its solution with that of the student and then it performs a diagnosis based on the differences. After giving feedback, the system reassesses and updates the student skills model and the entire cycle is repeated. As the system is assessing what the student knows, it is also considering what the student needs to know, which part of the curriculum is to be taught next, and how to present the material. It then selects the problems accordingly. 

Although there are many types of Intelligent Tutoring Systems around, each one must behave intelligently, not actually be intelligent. They must be able to:

• accurately diagnose students' knowledge structures, skills, and styles
• diagnose using principles, rather than preprogrammed responses
• decide what to do next
• adapt instruction accordingly
• provide feedback

The advances in the development of the computer has facilitated the use and design of intelligent tutoring systems. This proliferation of ITS has spawned many debates about their use and effectiveness.

• The Degree of Learner Control: How much learner control should be allowed in systems?
• Individual vs. Collaborative Learning: Should learners interact with ITS individually or collaboratively?
• Situated Learning: Is learning situated, unique, and ongoing, or is it more symbolic, following from an information-processing model?
• Virtual Reality and Learning: Does virtual reality uniquely contribute to learning beyond computer aided instruction or multimedia? 

Click on these sites to get more information about Intelligent Tutoring Systems.

• Intelligent Tutoring Systems
• Overview and Structure of ITS systems
• References on Intelligent Tutoring Systems
• Computer Based Teaching and Learning 

Hartley, J. & Sleeman, D. (1973). Towards more intelligent teaching systems. International Journal of Man-Machine Studies 2, 215-236.0 
Eric Thomas ，student, SDSU Dept. of Educational Technology