Books in the Monster Max series

Max and Peregrine volunteer at an old people's home when strange things happen. One resident is walking on the ceiling, another is riding their wheelchair through walls. And Reggie says his marmalade is haunted (no one listens)! Things don't look good: the Marmalade Ghost is turning into a sticky Godzilla... Time to 'Protect and Do Good Stuff!'

Max is just an ordinary boy, until he burps, when he turns into a huge monster, with teeth like swords, who can jump over buildings, roar and eat whole dustbins. But when something starts causing a lot of damage in his quiet suburb and it isn't Max, or his arch- nemesis Peregrine, Max has to find the real culprit...