Ari helps a neighbor who accidentally gets shrunk by Ari’s mom’s latest invention in this second book in the My Mad Scientist Mom chapter book series from acclaimed author-illustrator Jarrett Lerner.

Ari’s life is filled with school, video games, and his pet turtle, Fred: pretty run-of-the mill stuff. But not anywhere near run-of-the-mill is Ari’s mom, who’s a mad scientist. That’s right, a MAD scientist. Sure, she strives to make people’s lives better with her inventions, especially at home. But all of Mom’s inventions seem to go just the slightest bit off kilter.

His mom puts a new invention to the test to help clean up the clutter in their house: a magnimizer, which can shrink or enlarge anything! Pretty amazing, right? Well, not if you happen to be Mr. Jakes, their neighbor who comes face to face with this gizmo and becomes the size of a cockroach—and a potential tasty morsel for the resident basement mouse! Can Ari save the day and teeny-weeny Mr. Jakes?