America’s ballet scene has never exactly been bursting at the seams with homegrown talent. Indeed, compared with European countries, as well as with the former Soviet Union, the U.S. simply has no serious tradition of intensive dance training for talented young students. Ballet schools abound in the U.S. but few approach the level of the state-sponsored academies overseas. Now, the American Ballet Theater, which has traditionally filled its company with the best talent it can poach from other countries, is starting what it hopes will become America’s definitive school of classical dance.