What was the halftime show for the first Super Bowl I?

American trumpeter and bandleader Al Hirt performed, along with a high school drill team plus a couple of college marching bands.

The halftime show was produced by Tommy Walker, and featured trumpeter Al Hirt, the marching bands from the University of Arizona and Grambling College, the Ana-Hi-Steppers, 300 pigeons, 10,000 balloons and a flying demonstration by the hydrogen-peroxide-propelled Bell Rocket Air Men. In addition, the halftime featured a local high school drill team, the Ana-Hi-Steppers from Anaheim High School. The team joined the two university marching bands to form an outline of a United States map.

https://en.wikipedia.org/wiki/Super_Bowl_I

Super Bowl I played January 15, 1967, saw the Green Bay Packers victorious over the Kansas City Chiefs 35-10.

Here's a footage of the show:

https://www.youtube.com/watch?v=h8TxizeSzAU

The setlist:

- "The Sound of Music"
- Medley: "Way Down Yonder in New Orleans/When the Saints Go Marching In" (with Al Hirt)
- "Bugler's Holiday" (with Al Hirt)
- "Bury Me Not on the Lone Prairie"
- "William Tell Overture" (excerpt)
- "The Liberty Bell March"
- "Marching Along Together"
- "This Is My Country" (with Grambling College Marching Band and USC Chorus)

https://en.wikipedia.org/wiki/List_of_Super_Bowl_halftime_shows#1960s