Tips For Teachers


Jurtle is not just about Turtle Graphics. It is a simple yet flexible integrated development environment that can be used with other programming packages. In fact, Jurtle can support a full high school computer science curriculum.

Java Marine Biology Simulation


The Java Marine Biology Simulation Case Study (JavaMBS) is used as part of the high school AP Computer Science curriculum. Jurtle allows students to easily work with the JavaMBS. You can read about and download the latest version here.

After downloading and expanding the JavaMBS, use Jurtle to load the Code directory. This contains the main JavaMBS classes. Click the Compile All button to compile the classes in the directory. Now select the MBSGUI class in the class list on the left and click the Run button. This will invoke the class's main() method and bring up the GUI. See the above site for more information on how to run the simulation from the GUI.

Karel J Robot


Karel J Robot is a simple curriculum and robot simulation designed to teach fundamentals of object oriented programing in Java. You can read about Karel J Robot and download the simulation here.

Karel J Robot can be used within Jurtle with a few small modifications. In Jurtle, if you create a class that is not in the default package, it is assumed the java class file is in a directory hierarchy that mirrors the package hierarchy. This follows the recommendation by Sun, creators of Java. For example, the Karel classes are all in the kareltherobot package. Jurtle expects to find these classes in a directory called kareltherobot. However, this is not how the classes are currently packaged in the distribution mentioned above. To rectify the problem, take the directory that is created when you unzip the download (currently karelpriemer0309) and rename it to kareltherobot. You will also need to move the .java files in the goodies and testinfected subdirectories up into the kareltherobot directory.

Additionally, some of the classes make use of the separate JUnit testing framework. To use these, you will need to download the JUnit framework here and after expanding the .zip file, place junit.jar file in in the kareltherobot directory (or you can place it in the Jurtle's Extensions directory to make it available to all Jurtle classes).

The final modifications are to delete the Test and Test2 classes since they seem to reference a missing interface class (RobotTester) and will not compile. The StrategyTestMain class has a print statement near the end that references the non-existant variable aStatement. Just delete (or comment out) this line. Hopefully, these last modifications will not be needed in later releases of the Karel J Robot package since they appear to be programming errors.

After making the above changes, you should be able to click the Compile All button and get all the classes to compile properly. You can then follow the set of tutorials on the Karel web page.