And I'll tell you what I told Cassiopeia - any sufficiently advanced technology is indistinguishable from magic. What you do is also a science, and you'd be stupid not to acknowledge that.
Don't need to. We used the Eye of Harmony, which is what you get when you suspend time around an exploding star that's becoming a black hole, then harnessing the potential energy of a collapse that would never occur. The raw artron energy which comes from the Eye powers our TARDISes through the Time Vortex, via a link created with morphologically unstable living organic matter and acts as a point of reference from which both temporally and physically for all TARDISes to calibrate.
Boarding house sounds boring.
I'm not a Muggle? Which House are you? I'm guessing Sytherin?