Well if your doing a study group in French I would recommend going over materials that you know for certain your teacher will test you over. Like practice speaking French to each other on topics you know would be on the test. Point out and critique each other's mistakes if you hear any. Also, go over writing French. Make sure you have your grammar rules down cold and make sure you are writing your sentences correctly. Quiz each other over topics you aren't too comfortable with. Drill on your weak points and help each other out. For French, it's all about memorization and having things down cold in your memory.
