Oobi and Kako build a small version of their neighborhood out of shoeboxes and paint. They give Uma a tour and explain what everything is. Uma loves the tour, and they all sing a song about their neighborhood. — NickJr.com (source)
Oobi and Kako are looking through a flipbook about their neighborhood. The pages show a library, a post office, and a zoo. This gives Oobi the idea to make their own neighborhood. Kako is confused at first, but he starts to understand when Oobi takes out some cardboard boxes and paper. Oobi explains that he'll make a mini model of their neighborhood out of art supplies. Kako agrees to help, and they start to move boxes around and put things into place.
The next scene is an interview segment, where Grampu asks kids what they like to do in their neighborhoods. Afterwards, the boys put the finishing touches on their neighborhood model. Uma walks by and sees their creation. The boys decide to give Uma a tour of their neighborhood and explain each building. First, they go to the library. Oobi and Kako explain that you should be quiet in a library, since other people are trying to read. Kako puts on a wig and a pair of glasses, pretending to be a librarian. Uma checks out a book with the boys' help, and she gives "librarian" Kako a kiss to thank him.
Next, Uma pretends to send a letter at the post office. There, Kako acts as a postal worker. He helps her figure out how to address and stamp the letter. Uma kisses him again, this time just for fun. Finally, Uma visits the zoo and acts like different animals. Oobi dresses as an elephant, and Kako dresses as a lion. Grampu sees the kids playing and tells them how he loves what they've done. They all sing the Neighborhood Song as the episode ends.