Alone in His Teacher's House

While Mrs North, Marvin's teacher is on holiday, she asks him to look after her dog. Suddenly, Marvin has become the luckiest boy in school. He'll get to sniff about Mrs North's house, look in her wardrobe and rummage in her fridge. He gets paid $3 a day and he will get a bonus on top if everything goes smoothly. What could possibly go wrong?