- Not Dan tackles sixes in the seventh book of the series, Six-Po Joe. The numbers are getting bigger but even kiddos who convince themselves that math is too hard aren’t scared of birthdays. Birds eat bugs off of Six-Po-pot-amus’s so Eric created the colorful Six-Toed Six-Poed birds! Let your kiddo count the toes each birthday and put a simpler logic to that big number. Moe has a plan but that plan backfires! Birds fly away, Six-Po gets angry, Myrtle Turtle becomes a lawyer.. What are we to do? Don’t worry! Everything works out by the time Joe turns Sixty. Counting by sixes has never been so fun! Enjoy!