for one of my labs I have in my CS2 class at school, JCreator is installed on the school's computers with a 4.x version, I'm more of an eclipse person myself, I even use it at school in place of JCreator, but the file extension .jcp from what I know is a JCreator related file extension. What can I do to make a folder of files compatible with eclipse, which I use at home as well?
Eclipse identifies its projects by using two files namely .classpath and .project. As long as you can export those along with the project files and structure, you should be able to import a project into another eclipse instance.
I am not sure JCreator can create those files for you but I am sure that every eclipse project generates these files.
You can keep the JCreator specific files in the project folder(s), eclipse will ignore all the files that it cannot process/understand. The problem will be how to keep the libraries you are using in sync in both IDE environments as you edit your project.
You might want to re-factor that out to a build management tool like ant/buildr/maven