The 2011 International Summer School on AstroComputing was held by UC Berkeley and LBNL from July 18-29, 2011. This year's summer school focused on computational explosive astrophysics, including the modeling of core collapse and thermonuclear supernovae, gamma-ray bursts, neutron star mergers, and other energetic transients. Lectures included instruction in the physics and numerical modeling of multi-dimensional hydrodynamics, general relativity, radiation transport, nuclear reaction networks, neutrino physics, and equations of state. Afternoon workshops guided students in running and visualizing simulations on supercomputers using codes such as FLASH, CASTRO, GR1D and modules for nuclear burning and radiation transport. All students were be given accounts and computing time at NERSC and had access to the codes and test problems in order to gain hands on experience running simulations at a leading supercomputing facility.