Bait (adj and v, also spelt bate)
Means (adj) Something that is obvious, (v) risk getting caught.
Usage "It's so bait that you fancy Miss Simmons", "He'll bait you up to Miss Simmons"
Bait has long been a common slang term internationally, initially meaning suggestive female (hence "jailbait" for a young female). However, among England's youth it has been abruptly turned into either a questioning of one's intentions, or a plea to be more secretive, replacing the still legendary "grass up" in the process. Either way, much as in the like-worded worm bait on the end of a fishing hook, the implication is that the pupil in question will be caught if they do not correct their present course of action. Like, obviously.