A light-hearted story with some serious messages. Ideal for children and adults to share. 4/5 stars. 
 This review was originally published on my book blog: https://clairehuston.wordpress.com/20... 
 Many kids movies, particularly animated films, include jokes and references to appeal to parents and carers. These jokes usually sail over the heads of young viewers but keep the adults chuckling. In this way, while the film has a core children's audience, there's something in it for adults too. 
 I thought about this a few times while reading Time Travelling with a Hamster. I have no problem reading books which are written for children. I've always thought that a good book is a good book and can be enjoyed by a reader no matter how old they are. That said, in the case of Time Travelling with a Hamster, I'd say the book's core audience is definitely 8-12 year olds. Al, the main character and first person narrator, is twelve, and overall I felt the book read a little "young" for adults. However, the plot revolves around child-parent and child-grandparent relationships meaning that there is also a great deal for adult readers to appreciate and enjoy. Also, the action in the past takes place in 1984 with lots of little details which made me - a child of the 80s - laugh. I'm not sure many ten year olds would appreciate these period references. 
 It was interesting to read this book so soon after The Girl from Everywhere. Heilig's book gets around the difficulties of explaining time travel by being as vague as possible about how it works. Time Travelling with a Hamster takes the opposite tack: it dazzles us with Al's dad's knowledge of quantum physics and Einstein's theories in particular. It tries to explain time travel to you in simple terms... until you realize that you have little hope of understanding it all and happily give up worrying about it. Besides, I was too busy worrying about whether Al was going to get stuck in 1984 to really care how the laptop+tin tub = time machine set-up worked. 
 The story is great fun and includes solid moral messages such as the importance of standing up for yourself and your friends, being kind to animals, and cherishing your family. 
 Overall: this is a sweet children's story which would be ideal for an adult and child to read together. And it may even have taught me a few things about quantum physics!