Robert E. Wells uses a conversational tone and comparisons to illustrate largeness. He starts with showing how large a blue whale is in comparison to other large animals. Then, using humourous examples, such as blue whales in jars or 100 earths in a mesh bag, he relates those large things to even bigger things. The concept works, putting the size of our enormous galaxy and universe in perspective. 
This is a great book to kickstart size and measuring activities. Try a smaller scale, such as how many Cheerios it takes to outline a hand. To increase the complexity, find out how many Cheerios it takes to fill in the hand print, or to make it 3-D by stacking the Cheerios to the width of the hand. Don’t go for precision because this is a difficult fine motor skill, but a close estimate will get the point across.
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