George and Harold have played a trick or two on nearly everyone at Jerome Horwitz Elementary. When their latest prank causes the school's cranky cafeteria ladies to quit, Mr. Krupp hires a trio of unusual replacements - who happen to look an awful lot like aliens! Will that curtain-caped crusader, Captain Underpants, save the day once more? Or will those outer-space cafeteria ladies have him for lunch?

George and Harold are always good at using their imaginations, and that drives their mean homeroom teacher, Ms. Ribble, crazy! But this time, they've come up with much more than a silly prank...With her horrendous hairdo and two rabid robots, Wedgie Woman is well on her way to world domination, and only the Waistband Warrior can stop her!

The teachers are nice, the cafeteria serves delicious food, and the school principal, Mr. Krupp, thinks George and Harold are hilarious. Something is very, very wrong - and it gets even wronger when the boys' pet pterodactyl, Crackers, and Sulu the Bionic Hamster are captured by George and Harold's evil-twin look-alikes. Now George and Harold must face their greatest foes yet: THEMSELVES! Can they handle this mess on their own, or will they need Captain...

George and Harold are behind bars for a crime they didn't commit! But just as they are settling into their new life, they are pulled from prison by a time-traveling tyrant named Tippy Tinkletrousers! Now the boys are taking a trip back in time to the carefree days of kindergarten, when the scariest thing they had to face was not evil mad scientists or alien cafeteria ladies but a sixth-grade bully named Kipper Krupp, the nephew of their clueless school...

Ricky Ricotta and his Mighty Robot are ready for the best day ever! Today is Ricky's birthday, and it's off to a great start! After peanut-butter pancakes and presents, Ricky's parents are taking him and his Mighty Robot to see dinosaurs at the museum. And they have a surprise for Ricky: His cousin, Lucy, is coming with them! Ricky thinks Lucy is a real pest. Suddenly, things aren't looking so sunny anymore. At the museum, there is another surprise...

Ricky Ricotta, a small mouse, is being bullied at school, but when he rescues a powerful robot from its evil creator, he acquires a friend and protector--and saves the city from Dr. Stinky.

Infuriated by the declaration that Pluto is no longer a planet, President Penguin and his penguins invade Earth and it is up to Ricky and his robot pal to defeat them--with some help from Ricky's cousin Lucy and her pets.

By flipping the pages, the reader may view animated illustrations that follow Ricky Ricotta, a small mouse, his giant flying robot, and his annoying cousin Lucy, as they battle the nightcrawlers from Neptune that are invading through a wormhole.

Ricky Ricotta, his Mighty Robot, cousin Lucy, and some friends set out to save mousekind from Stupid Stinkbugs from Saturn, with a little help from some special gum and taffy.