YA/kids' book featuring a kid and an alien whose preferred pronoun is "it" rather than "he" or "she" [duplicate]

Question

There's a book I read in the late '90s that I'm trying to remember. Here's what I remember:

An alien whose preferred pronoun is "it"

The scene I remember very vividly is one of the aliens telling the point of view character (a kid, I think) that it would be ruder to call it "he" or "she" than to call it "it".

A space ship that shrinks

The aliens used a device so that they are shrunken / miniaturized to be very small, and the device to make them big again is broken. They shrink the POV character to their size to be able to be on their tiny spaceship.

Rocket belts

They teach the boy how to use a rocket belt, and he learns it pretty easily but never becomes an expert at it.

The aliens are chasing a criminal

The aliens are chasing an alien criminal who they think is hiding on earth. The draft the kid and deputize him. The bad guy's crime is cruelty.

Answer 1

Might this be Aliens Ate My Homework (1993) by Bruce Coville...?

This review contains a good summary of the plot, confirming the interaction between a schoolboy and tiny aliens in a miniature spaceship:

Sixth-grader Rod Albright, better known as Rod the Clod among his classmates, is a target for the two bullies at school and the go-to babysitter for his toddler twin brother and sister at home. One day, while working on a science project for school, a miniature alien spaceship crashes into his window, and Rod is commandeered into helping the alien crew in their search for BKR, an intergalactic criminal infamous for his cruelty – and who just happens to be hiding out in Rod’s neighborhood. Can Rod, who is incapable of lying, keep his alien visitors a secret and help them succeed in their mission while getting his science project done on time?

And having checked a preview of the book, I can confirm that the alien does state that it would prefer to be referred to as "it" rather than "he" or "she":

I turned to Madame Pong, but she just spread out her hands. "I don't think you want to get into a discussion of biology as it is practiced on Tar Gibbons's planet."

"Okay," I said. "Just tell me what pronoun to use when I'm talking about him. Her. Uh, it. I mean ... see what I mean?"

"It will do just fine," said Tar Gibbons.

"What will do just fine?"

"It will," he repeated.

"What will?"

"It. Refer to me as an it."

"That seems pretty rude," I said nervously.

"Not as rude as calling me a he or a she," it said.

Searching the preview also brings up results for a "shrinking ray" and a "rocket belt".

The book was subsequently adapted into a movie. Here's a trailer, introduced by William Shatner: