The colonies developed a free-market economic system with little control from England initially. Children would apprentice with skilled workers after basic schooling to learn trades. Indentured servants who could not pay for passage to America would work for families for several years to pay off their voyage. Slavery began small but grew significantly as the tobacco industry expanded and plantations for crops like rice and cotton developed, requiring large amounts of cheap labor. By 1700, over 28,000 slaves lived in Virginia.