My biggest pet peeve with books for young children is when they try to simplify the information so much that they over-simplify it to the point of misinformation.  This book is all about how the scale on a map sets the distance represented on that map.  Then they draw the maps with giant sized icons that don’t fit the scale — one map makes it look like a road is half a mile across, and one makes it look like a bird cage is 20 feet tall.