Are you currently on B1/B2 visitor status and would like to attend a U.S. school?
Under the current regulations anyone with B-1/B-2 status may not study in the US. It is required that they first obtain F-1(academic student) or M-1 (vocational student) status.
To apply for a change in status: you must not have already enrolled in classes (this is considered a status violation and you will be unable to extend or change your status), must have up to date status, and have not been involved in any illegal employment.
A status change from B-1/B-2 also requires a fee and filing out the proper paper work (Form I-539).
If you do not meet the criteria for obtaining an F-1 or M-1 status, you may be able to apply at a consular post abroad.