You need to ensure you are licensed to conduct such activity in each state you either advertise in, do business in or both. By do business in, I mean you will have contact with consumers in other states. You need to register with the secretary of state in each such state and if the department of education in each state requires you to have a particular license, then you need to ensure you have that. Talk to a business attorney in the state in which you plan on starting and understand that you will need to get your business plan together and contracts and fee structures together before you embark on taking on even one customer.