Books like Ricky Ricotta's Mighty Robot Vs. the Uranium Unicorns from Uranus

Dav Pilkey is one of my son's favorite authors, he has read all of the Captain Underpants series and most of the Ricky Ricotta series. Last night for bedtime we read #7 in the series. The Ricky Ricotta series seems written for the age group just below the Captain Underpants age group. It was a fun adventure with an underlying theme of not taking friends for granted. The illustrations were perfect for the story and there was some flip-o-rama as well as "how to's" for drawing the characters. Both of my kids (boy 9 and girl 7) loved it and gave it way more than 5 stars.