Saskia : The first book in the Saskia story

Richie is falling, he's certain to be killed as he hits the bottom of the quarry he's tumbled over the edge of. His life is saved by the intervention of a disembodied being he eventually comes to call a Guardian of Reality. But there's a snag. The voice gives him super powers, so he isn't hurt by the fall. Trouble is, it isn't super powers like Superman, it's super powers like Supergirl, which comes as a bit of a shock as you might imagine. Richie decides to put up with being a girl, having super powers does have the odd advantage. He calls himself Saskia and everything is fine - until he meets the 'real' Saskia. Saskia Hunt is a real thirteen year old girl, while Richie is only a pretend thirteen years old. The two Saskias quickly become firm friends. A friendship that survives Richie having to explain to Saskia about not actually being a girl. At this point Saskia is apparently so upset that the Voice that fiddled with Richie changes her as well, now there are two super girls. Despite the difference in age and even in gender, the two girls, Richie in his form as Saskia, remain best friends. Now the fun begins as Saskia Chandler has to learn how to be a girl. Almost the first thing that happens is a full formal evening event that sees her stuffed into a long frock and required to be a girl in front of a whole crowd of people. Quite apart from this crash course in being a young girl, Saskia Chandler finds that she and Saskia Hunt need to use their super powers to aid others as well as themselves. They never actually discover why they've been changed to be more than human, but get the occasional inkling as the Voice gets them to do things it can't apparently do for itself. This includes being shuttled around in time and space and saving the whole world - twice!