Preface 
Introduction 
1 Learning Environments: Now, Then, and Someday
Robert W. Lawler
2 Algebra Slaves and Agents in a Logo-Based Mathematics Curriculum
Wallace Feurzeig
3 Artificial Worlds and Real Experience 
Andrea A. diSessa
4 Microworlds: Transforming Education 
Seymour Papert
5 Computer Microworlds and Reading: An Analysis for Their Systematic Application
Robert W. Lawler and Gretchen P. Lawler
6 Learning With Interactive Media: Dynamic Support for Students and Teachers
Margaret M. lUel, Ja.mes A. Levin and Barbara. Miller-Souviney
'1 An Example-Based Environment for Beginning Programmers
Henry Lieberman
8 Object-Oriented Logo 
Gary L. Drescher
9 Design and Use of a Constraint-Based 
Laboratory in Learning Design
Mark D. Gross

10 Intelligent Tutoring Systems: An Overview
Masoud Yazdani
11 Some Principles of Intelligent Tutoring 
Stellan Ohlsson
12 PIXIE: A Shell for Developing Intelligent Tutoring Systems
Derek Sleeman
13 T he Application of Machine Learning to Student Modelling
John Self
14 Qualitative Models and Intelligent Learning Environments
Barbara Y. White and John R. Frederiksen
15 Sense and Reference in the Design of Interactive Illustrations for Rational Numbers
Stellan Ohlsson
16 Computers Teaching Programming: An Introductory Survey of the Field Benedict du Boulay and Christopher Sothcott
1'1 GUIDON-WATCH: A Graphic Interface for Viewing a Knowledge-Based System
Mark H. Richer and William J. Clancey
18 Teaching a Complex Industrial Process
Beverly Woolf, Darrell Blegen, Johan H. Jansen, and
Arie Verloop