The Corot satellite observed the young stellar cluster NGC 2264 during 23 days in March 2008. This was the first time a group of young accreting stars, classical T Tauri stars (CTTS), were followed ininterruptedly with high photometric accuracy for such a long run. Before the Corot observations, AA Tau (Bouvier et al. 2003, A&A, 409, 169 and Bouvier et al. 2007, A&A, 463, 1017) was one of the few CTTS systems that had been analysed synoptically over several consecutive rotational periods. Its analysis suggested a highly dynamical star-disk interaction mediated by the stellar magnetic field, as predicted by magneto-hydrodynamical simulations of young accreting systems.