The guard dogs haven't seen a sign of Wolf in weeks, but D.O.G. can't shake the feeling that something wicked will try to ruin the pups' Graduation Day.

The greatest friendship on earth is at risk when the constellation that powers Pup Academy fades out and humans no longer want dogs as best buds.

When the pups share stories about their owners, Spark struggles with her shortcomings. But can she fake it to impress her professors and classmates?

Pup Academy celebrates a special day of student reviews, Charlie shares a meaningful gift with Morgan, and King's dark past comes to light.

It's a ruff day for Corazon when a surprise guest follows in his footsteps and challenges the rules. Meanwhile, Morgan tries some new gadgets.

Class is officially in session after the wise D.O.G. recruits a new group of canine classmates. Elsewhere, young human Morgan learns about the academy.

While Corazon struggles with an awkward accessory, Morgan and Izzy make a major mistake that threatens the fantastic future of Pup Academy.

A sick day for Morgan means an adventurous day for his friendly fill-in! Meanwhile, the pups get playful with a collection of creative pranks.

Morgan's schedule gets messy when he's asked to support the academy and his own school duties. Also, the pups take a pop quiz. Let the chaos begin!

Corazon lands in an im-paws-ible situation when he tells a lie to impress his crush, Pom Pom. Will he come clean before the Pup Academy talent show?

The pups pair off and partner up for an academy-wide scavenger hunt. But when Morgan and Spark stray from the path, things take an eerie turn.

A new day dawns on Wolfehead as Spark encounters King. At the academy, the pups learn about baby talk ... and try to understand why humans love it.

As Izzy grows suspicious of Corazon's daily routine, Charlie takes D.O.G. out for the day — and leaves Morgan with a long list of responsibilities.

Ready for a purr-fect rivalry? Whiz, Corazon, Spark and the rest of the pups learn how to coexist with nature's enemies: cats.

Spark explains her side of the story after leaving the Academy, but Corazon and Whiz soon find out it was all part of Professor Fitz's sinister plans.

Everyone thinks Spark is the Chosen One according to school prophecy. But since Spark spent her life as a stray, she's not used to special treatment.

Some uninvited guests look to stink up this year's Howlathon during the harvest moon. But Corazon has a smelly secret weapon to stop them.

The pups need all the extra paws they can get to help break King out of Animal Control when he's snatched up after his hideout is suddenly raided.

It's the Howlers vs. the Growlers on the fetchball field. Will Spark be the first stray to win the MVP trophy, or will Bite take the title once again?