The Galileo Teacher Training Program (GTTP) is a living legacy of IYA2009. As a cornerstone of this important moment in the history of Astronomy, GTTP has managed to name representatives in over 100 nations and reached over 15000 teachers at a global level. The model used so far ensures sustainability and a fast growing support network. The task at hand is to engage educators in the use of modern tools for science teaching. Building the classroom of tomorrow is a promising path to engage young minds to the beauty of science and space exploration.