conversation process from toursits b1/b2 visa to student.

[anki2012]

im 20 years old .... i came here in november in visiting visa b1/b2 and its going to end in may and my question is to ask how much time does it take to extend visa from visiting to student....., and if i start processing now to do it thus it get complete?.....CAN I HAVE TO TIME TO EXTEND IT ? waiting for ur reply, please help me. thanks.

[anki2012]

how much time does it takes and my visa ending in may... does it possible if i start process now to extend it....! pls help me.