We used it to compliment our grade 4 study of physics. It was tons of fun for our kids to learn about bridges, rockets, airplanes, roller coasters (and so much more) in a hands-on way.
This is a great book if you're looking for simple and quick exploration activities to support engineering concepts related to radiation, acoustics, hydrology, meteorology, and more.
Each activity is simple and involves things easily located or found around the house.
Each begins with "What You Need to Know" that is very helpful for background knowledge and vocabulary. It is written clearly and can be readable, while not being diluted.
There are a couple of exercises that test the students understanding of the material. These often involve studying diagrams that are well drawn and to the point.