What performers have played the Super Bowl halftime show twice? And which performer has done it 3 times?

There was a group of performers called "up with people" that performed 3 times I do not know if that would count.

That one I knew off the top of my head for the rest I had to look on the page below.

Florida A&M performed twice

University of Michigan has performed twice

Gloria Estafan twice solo and once as part of the Miami sound machine.

--- Edit

Nice call with Grambling but they have only done it twice. They also have a pre-game show to their credit but that was not the question ;)

The Grambling State University band and Up With People have both performed three times. I'm not sure who else, if anyone, has done it more than once.

Edit: Grambling was part of the halftime show at I, II & IX.

Edit again: My mistake. I had always heard they were part of the halftime show at I.

Final edit: Weren't they part of the show at XXXII?

Grambling State-2 (, II, IX)

Florida A&M-2 (III, V)

U of Mich.-2 (I, VII)

Justin Timberlake-2 (XXXV, XXXVIII)

Gloria Estafan-3 (XXVI, XXIX, XXXIII)