Zach is injured when Amp, the alien he is hiding, borrows the brake cable from his bike. Amp used it to work on a machine he needs to get back to his home planet.  While he is incapacitated at home, Zach has to figure out how to do his homework, how to help Amp get back to his home planet and stop the invasion of Earth, and how to keep his nosy little brother from finding out about Amp.

This is a funny, fast-paced little book for grades three through five.  Nate Ball, a mechanical engineer, introduces the reader to several science concepts and vocabulary that supports the concepts he has introduced.  He has also, at the end of the book, included an experiment on building an egg decelerator. The information is easy-to-read and should be fun for any student interested in science

The reader is also given a preview of the next book in the series following the experiment. This preview will cause young readers to beg for the next book in the series. I would recommend the purchase of On Impact! for any elementary library.

The reader or teacher can also find Common Core resources for this book at http://www.readcommoncore.com .