Student visa
I have student visa and want to come to the US earlier than that 30 days allowed period of time.Probably one month earlier.Can I enter on visa waiver and before school starts re-enter the US by going to mexico or canada to activate the student visa? (which i was told i need to do).if i do so,do i need to buy one way or round trip ticket since i do not need to go nack to europe to re enter the US and how do i explain it to the immigration officer that i only have one way ticket? a while ago i learned i need to obtain change of classification and fill form I539 which takes months.is that so?