A.J. and his friends get a Personal Digital Assistant named Miss Porter as a substitute teacher, who can order pizza and tell endless jokes, but grows power-hungry when her system is changed and tries to take over Ella Mentary School.

Principal Klutz has invited a special guest to Ella Mentry School. Her name is Miss Aker, and she's going to show A.J. and his friends how to create cool things out of materials like balloons, straws, and even Popsicle sticks! But what happens when they make a robot so smart, it plans to rule the world? Can anyone stop it?!

There's a new principal at Ella Mentry School. Yes, it's true! Mr. Klutz is retiring and the president of the Board of Education, Dr. Carbles (Boo! Hiss!), has hired the best person for the job -- or at least the funniest. But stand-up comedian Mrs. Stoker will have to face Vice Principal Mrs. Jafee in a big joke-off duel to defend her new job. Will Mrs. Stoker have the last laugh? Or will shoe lose her audience when things get serious?

"After noticing that A.J. and his friends' geography knowledge could use some work, Mr. Cooper invites to class just the person to help. Globetrotter Mrs. Barr speaks seven languages and has visited nearly two hundred countries! But why does she carry a suitcase everywhere she goes? And why does she open a window whenever she walks into a room? Perhaps Mrs. Barr has something to hide"--Provided by publisher.