"The Secret Ceramics Room of Secrets" is the tenth episode in Season 8, being the one-hundred-and-thirty-ninth episode overall.
When the kids are given the task of making homemade gifts for their grandma's birthday, they set out to find a secret room filled with homemade ceramics which, according to urban legend, has been boarded up for years at their school. Meanwhile, Teddy moves his phone repair service into the restaurant.
The episode starts in the kitchen discussing Linda's mom's birthday. Linda tells the kids not to make poorly done gifts for her this year. Bob tells them not to do the same to his dad.
At lunch, the kids start discussing a legend about a wall built over a ceramics room that was burnt right before a school board inspection. They consider breaking into the room to get the hand-made gifts. The kids ask teachers, who all deny it happened, while the librarian suggests they look for it. A coffee mug he stole from the lounge had a name on it, and the visit the person who made it, and she says it did indeed happen. She offers them her yearbook as they leave, and they decide to use it to find the room.
They successfully find where the wall was, under some lockers in that hallway. They agree to break a hole in the wall of the room next door to it. After breaking it, they discover it leads to a broom closet. They look closely at the picture, and realize that it’s backwards and the room is in between the science and math rooms. As both are occupied during lunch, they begin to plan to break through the lockers.
When they get home, they ask Teddy how to cut through a locker. He gives them instructions and lends them the tools they need (they claimed to have dropped a penny behind it). They successfully break through the locker and wall, and discover the legend is true. Mr. Frond then discovers them doing this.
Frond brings them to his office and tells them he's calling their parents. Louise notices he took the flashlight and saw, but not the other tools. They find him taking a vase, and discover he rigged the class secretary election. He agrees to not punish them if they keep it a secret. Louise decides not to do it, and they make the gifts in the pottery room. Their grandparents say they love the gifts.
Teddy moves his business repairing phones into the restaurant, and proves to be annoying while working. Teddy annoys Bob by clogging the employee toilet and trying to break down the door. He then accidentally launches a screw and searches a customer's food then under his seat for it. Teddy decides to do the job at home, calling Bob "annoying to work with".