Pinocchio's Promise is Volume 3 of the Walt Disney Fun-to-Read Library.
Geppetto finishes work on a clock for Mrs. Romano and assigns Pinocchio to deliver it. As he and Jiminy make their way across town, they do not notice Foulfellow and Gideon spying on them. When they hear Pinocchio wishing that he could go to the circus, Foulfellow picks up two old circus tickets off the street and then tells Pinocchio that he'll deliver Mrs. Romano's clock and has Gideon take Pinocchio to the circus.
After bringing Pinocchio to the circus, Gideon deserts him, and the ticket taker scolds Pinocchio for trying to get in with an old ticket, so he runs through the circus, losing Jiminy on the way. While trying to find Jiminy, Pinocchio gets splashed by the elephants, tossed in the air by the clowns, lands on the back of one of the horses, and is dropped into a pile of hay by the circus strong man. Then he wanders into the one of the tents and gets nabbed by the lion, but fortunately, Pinocchio's wooden scent reminds the lion of his old wooden ball and manages to tame the beast. After making it out of the tent, Pinocchio reunites with Jiminy and gets scolded by the ringmaster for wandering into the lion-taming act.
After some reminding from Jiminy, Pinocchio remembers his promise to Geppetto and heads back to town. He tells a policeman about Foulfellow taking the clock from him, and they catch the fox before he can sell the clock. As the policeman chases after Foulfellow, Pinocchio grabs the clock and delivers it to Mrs. Romano. When Pinocchio and Jiminy finally return to Geppetto's workshop, Geppetto reveals that he was planning to take them to the circus after they finished the delivery, but it's too late to go now. Pinocchio, however, says he's learned a valuable lesson and vows to keep his promise next time.