25 November 2016 Last updated at 10:36 GMT
Teachers are hoping he'll help pupils learn the school's core values of respect, compassion and empathy.
Watch co-head Tristan Merriam take the register with Gatsby - Mr Merriam's also the lucky one to take the puppy home.
Gatsby the dachshund is starting school - he's only eight weeks old but the children at Tickenham Primary School have been very welcoming.