Concept Modeler

A tool for the creation of interactive online tutorials about conceptual models.


The following conceptual models are supported:

  • Conceptual Entity-Relationship Diagram
  • Relational Entity-Relationship Diagram

Using Concept Modeler, a taecher can create a tutorial page consisting of:

  • Instructional text, consisting of a problem description and instructions for the student
  • A problem diagram
  • A solution diagram

When the tutorial page is presented, a student can:

  • Read the instructional text
  • Edit the problem diagram
  • Retrieve a textual description of the differences between the current edit of the problem diagram with the solution

The tutorial page can be exported as a SCORM Sharable Content Object. Using additional tools, this allows integrating the tutorial page into a larger online tutorial, bundling it up into a SCORM Package Interchange File, and deploying it on an online learning management system.

State of this Project

This project is in an experimental state. Do not use it for the creation of real learning content, as you might face issues with the tutorial pages once you deploy them. Also, we do not guarantee backwards compatiblity of XML source files created using the tool.

  • Except for the simulation, Conceptul and Relational Entity Relationship Diagrams are fully implemented.
  • Support for additional diagram types has been started, but not finished: Relational Data Manipulation Language, UML Class Diagram, UML Activity Diagram, PERT Diagram.
  • The exported SCORM Sharable Content Object do have a generic layout. For a final release, a template mechanism needs to be added, allowing to integrate the pages created with Concept Modeler into the graphical design of learning content produced by other tools.


Concept Modeler is dual-licensed under the GNU Lesser General Public License LGPL and the Creative Commons Attribution 3.0 License.

History of this project

Concept Modeler is a remnant of a project application, which was made at the Lucerne University of Applied Sciences and Arts (HSLU) in 2001. Unfortunately, the project was not admitted, but I had already put a considerable effort in my spare time into the prototype for the class diagram editor.

In 2006, the project seemed to become a revival, as part of a collaborative project between HSLU and the Scuola universitaria professionale della Svizzera italiana (SUPSI). Unfortunately, HSLU had to back out of the project in 2007. The result of this collaboration were two concept modeler tools for entity relationship diagrams.

And finally, also in 2007, Florian Padrun, has contributed the editor for activity diagrams to this project, as part of his diploma project at HSLU.




for Entity-Relationship diagrams:

Java Webstart

for UML class diagrams:

Java Webstart



Concept Modeler Source Code

other 2.3
15.5 MB




Entity Relationship:

Demo Tutorial
A very crude demo tutorial.

UML Class Diagram:


An account class and an instance. Messages can be dropped on the instance to deposit and withdraw money.


Concept-Modeler for Conceptual Entity-Relationship Diagrams (Click image to zoom).

A SCORM Tutorial built with Concept-Modeler for Conceptual Entity-Relationship Diagrams (Click image to zoom).


© Werner Randelshofer. All rights reserved.