@logiccolor,
As jespah and Linkat mention, AP classes and college classes through a local college or university. Both of these are also good for students going along at a regular pace (starting on time, no years of being held back). The college courses in particular, immerse the student into the next level of education and get them some credits before hand, so, they can go at a full 4 years with reduced workload each semester or finish off in just 3 years.
Once in college, a student can, in many places, also take classes during the summer (which my nephew also did).
