The Last Kids On Earth Series Books 1 - 7 Collection Set By Max Brallier:

Last Kids On Earth:
‘Forty-two days ago I was an ordinary kid, living an uneventful life. But now it’s TOTAL MONSTER ZOMBIE CHAOS and I’m battling beasts on a daily basis. Crazy, right? But I know exactly how to make it through the zombie apocalypse.’

Zombie Parade:
It’s still TOTAL MONSTER ZOMBIE CHAOS on the streets, but now Jack has a gang of friends to help him through – science genius and best friend Quint, super-strong Dirk and all-round coolest girl ever, June.