Kinney is credited with designing and developing the online virtual world Poptropica, which features various themed islands and interactive games for children. It has been a popular platform for educational and entertainment content.

Jeff Kinney and his wife, Julie, opened 'An Unlikely Story', an independent bookstore and cafe in Plainville, Massachusetts. The bookstore is a community hub that hosts author events, workshops, and other literary activities.

Kinney established Awesomeness Fest, a festival held annually in Plainville, Massachusetts, and is focused on celebrating books, creativity, and community engagement. The event includes author talks, book signings, and interactive activities for fans of all ages.