Ratso is a male rat character who appeared in JumpStart Math for Second Graders and the workbook JumpStart 2nd Grade Math Workshop.


In JumpStart Math for Second Graders, Ratso has white fur, a red nose, and light pink eyes. He wears a tunic that is light gray on the right side and darker gray on the left side, with a row of red triangular trim pieces at the bottom. He also wears red gloves, red boots, and a long olive-green cape.

In JumpStart 2nd Grade Math Workshop, Ratso is much fatter and has orange fur. He wears a simple red garment, red shoes, a purple cape, and lavender gloves.


Ratso thinks highly of himself. He is constantly scheming and creating traps for CJ.

In the Game

Ratso is the main antagonist of JumpStart Math for Second Graders. He takes over the kingdom and casts a spell that traps all of the royal subjects except the Princess in a mirror. Then he declares himself king. CJ and Edison are out to foil his scheme and bring order back to kingdom.

Ratso has set up several traps called 'Ratty Challenges' around the castle. These are challenges that CJ and Edison must complete, or else they'll be sent to the dungeon. Ratso also has four henchmen who are also rats. They mainly appear in the Banquet Hall activity, although sometimes a henchman will appear to give CJ a challenge. Each time the player collects an ingredient for a potion or frees a Royal Prisoner, Ratso will appear in a short cutscene to express his displeasure or taunt CJ.

The player can't enter Ratso's lair until they have freed all of the Royal Prisoners and collected 100 bravery points. Then the player can challenge Ratso. The player has to beat Ratso in a game of Tic Tac Ratso. After CJ wins, Ratso and his henchmen are all shrunken down to the size of normal rats. Ratso rants and vows his revenge, but CJ just puts a cage over Ratso and his minions.

In Books


CJ and Ratso in JumpStart 2nd Grade Math Workshop

Ratso appears in JumpStart 2nd Grade Math Workshop. Rather than trying to rule the castle or using any magical mirrors, he is simply competing in a royal tournament with CJ.


  • "Everyone knows Ratso knows all."
  • "No one beats me, see? No one! Looks like I'm going to have to teach flipper boy to show a little more respect."
  • "You think you can get this castle back to its rightful owners? Think again."