check your student handbook but at most schools they have the right to search you as long as they have a reason to for instance if you have a history with drugs and they feel like you are dealing you may be asked to search your locker etc.. the best thing to prevent all of this would be to delete all of your text messages before your phone is taken, if they however get a friends phone and call u up to the office deny that thats your # they can't proof it without doing some research and quite honestly i doubt they go through that much trouble. but in the end sending nude pics via phones is very risky and your better off doing it over the computer, and don't send out pictures receiving them is fine because you can't prevent that but sending around another girls picture can get you in some deep shit! remember someones always watching so be carefull what you do via your phones and online,many believe the government has access to all of our texts!