Emma has been 'gone' several times, spending a long time in a coma, kept in a sort of shrine by Sebastian Shaw and protected by him. She recovered (don't ask me how) just in time to receive Kitty Pryde during her visit to the Massachussettes Academy with Doug Ramsey. This "visit" was not very pleasant for the girl, for she was kidnapped and Doug had his perceptions altered, seeing no danger. Since the X-Men were in the Secret Wars, she had to be rescued by the New Mutants, who finally had their first confrontation against the Hellions.
She had several combats against the X-Men, but entered a catatonic state after a fight, during which her group of students was massacred by the evil mutant Fitzroy. Then, the X-Men rescued her body from Fitzroy and took it to Xavier's Mansion. She recovered some time later, taking for a while the body of Iceman and, discovering the fate of her pupils, decided to take under her care the new generation of young mutants. Joining Banshee during the Phalanx Covenant, they formed Generation X. Since then she has been the stern teacher she thinks the kids need, as Banshee is more like the friendly uncle. She has been involved in all sorts of things like trying to find out as much information on Penance as possible by invading her mind, doing the same to M, being attacked by salad, "revealing" all of herself to Sean, fained death to fake out Black Tom Cassidy, and (this is the worst) tryed to cook for her students when they were under her sub-conscious control. Yeek.
It was recently learned that when Ms. Frost, here, was young and just learning her powers, which was assumingly some time after escaping the mental institution her parents put her in, she ran into Banshee and a very unlikely friend; the Dark Beast. Apparently, when the AoA Beast went through the M'Kraan crystal before the destruction of his reality, all the strain caused him to lose his memory. And when a sixteen year old Emma was in trouble with some hormone-driven boys, he saved her as she was not at even half her potential regarding her mutant power. This confrontation caused Sean Cassidy, former Interpol agent turned NYPD officer, to take action in the middle of his investigation on Henry Leland, a member of the New York section of the Hellfire Club. That was the first time Emma came in contact with her future partner-in-teaching.