It's Fonzie's birthday, and past clips are shown as the gang reminisce.

The gang organizes a surprise party for Howard and Marion's 20th anniversary as clips from previous episodes are shown.

Lori Beth has to write a term paper on the typical, middle-class family, so she interviews each Cunningham family member as well as their friends as clips from past episodes are shown. Fonzie says he'll tell Lori Beth something nobody knows about the Cunninghams.

Celebrate the 20th Anniversary of Happy Days, one of America's favorite TV shows, with members of the original cast. Includes personal recollections and film clips. Stars featured: Ron Howard, Henry Winkler, Tom Bosley, Marion Ross, Anson Williams, Danny Most, Noriuki "Pat" Morita and Scott Baio.

In this two-hour reunion special, various clips are shown from past episodes, and cast members recall memories from their time on the show. Also included are highlights of a reunion softball game played by members of the cast as well as a cast reunion at Arnold's Drive-In.

Mork returns to 1950s Milwaukee to learn about relationships in this retrospective episode.