Zak is super fast and zooms around the galaxy, but where will he go Also, Mack the dog likes to run, but sometimes he runs too far! Written by Jenny Jinks, this educational Early Reader book is book band Red (aimed at 4-5 years, Reception grade).The colour grading system is recognised by the Institute of Education which reflects the reading difficulty. The book content, language style, phonics and layout are taken into account to determine this.