As Director of the PhET project, I want to take a moment to reply to your comment about a "not-so-open community". Our project is dedicated to providing openly licensed simulations, and you can find those on our website - used 250 million times per year globally. The PhET simulation code is necessarily complex, but powerful. We use an open license with the code so that others can leverage our libraries, but we are largely grant-funded and are a small team, so our focus is necessarily on moving our grant work forward, producing simulations, and making those available for the world. We do our best to address reported problems in using our code, but at the moment, we have very limited resources to provide additional support.
This week we received a new grant to begin to evaluate the prospects of fostering an active open development community around the code base itself. So your interest in the code is well timed. Please email phet...@colorado.edu
to introduce yourself and where your interests lie in participating in an open community around the PhET codebase, and we will pass it onto the grant team.
Best, Kathy Perkins
Director, PhET Interactive Simulations