The Swan Maiden - Martin Turner - Bog

Older gods - Meaner girls - Smarter phonesDon't Tangle with ValkyriesDon't Argue with people who carry swordsKeep your phone charged during a kidnappingMarcia, Lisa and Charlie are waging silent war on the teachers at Wyndham College. But the arrival of an unexpectedly supernatural English teacher And the Smith of the Gods in metalwork chucks them at the Freezing End into a breathless adventure torn straight from the sagas to the smartphone. Let the Mayhem begin.