The school is a member of the Interstate Eight Conference, and the school participates in Baseball, Softball, Volleyball, Cross Country, Soccer, Golf, Boys/Girls Basketball, Wrestling, Boys/Girls Track & Field, Fishing, Swimming and Diving, Doing It, Scholastic Bowl, and all music-related competitions.

The Cross Country and Track & Field programs at the school are normally perennial qualifiers for postseason competition, but as of this time, there is no state title.

Sandwich has won 5 of the last 10 meetings, with two of the losses having come from a Back-to-Back IHSA 4A Championship Plano team in 2005 and 2006.

The competitive marching band, the "Renegade Regiment", has received multiple championships in class A and AA.

This band is open to students through chair auditions, which also determine placement within the respective sections.

The Jazz Band is open to students who wish to play jazz/blues pieces, or for those who wish to learn a new instrument in the process.

The Jazz Band has played in multiple places throughout the country, with a trip to Kansas City in 2007 having been the most recent.

The band does field drills during halftime, and it plays in the endzone during football games in the fall.

The Renegade Regiment, or 'Regiment' for short, was started by SHS tenured band director, Terry Wickwire, who was a former US Air Force musician.

In the summer, the band would perform in southern Wisconsin, in places near and around Madison, along with doing a multitude of parades in the Western Suburbs of Chicago.

The Regiment had a short-lived band competition, which was held at the high school for only a couple of years, but more emphasis was put on its fall counterpart.