New contributors should read this page carefully.
You must follow the coding guidelines described in those links:
If you want to develop a new activity for GCompris, a good start is to follow the instructions on this page : An exercise for new contributors.
Always look at existing activities, and take a look at their code when you have a problem. You have to think by yourself, try and fail to find solutions. This is not a school assessment.
We can only provide limited feedback to get you started.
To create a new activity, you will need to develop it by yourself. Think about making a detailed mockup, that will help you solve the main design questions, and make it easier to communicate the idea. Then, once the mockup is accepted, of course you will have to work on it. When you have a prototype of the activity almost working, then we can provide a little more help if needed.
For the graphics, if you can, try to follow the artwork guidelines. In any case, once an activity is ready, the images have to be checked and updated by our main artist.
Please use the mailing list to share your thoughts, issues, and wishes to our community.
Note: If you plan to apply for next GSoC, please check GSOC newcomers, and especially the last paragraph.