* Definition of "high school": The definition of a high school can vary slightly by state.
* Definition of "sports": Some schools might offer a few sports while others have extensive programs. A school with only one club sport could still be considered to have "sports."
* Data collection: There isn't a central, constantly updated database tracking every high school and its sports offerings.
While we can't give an exact number, it's safe to say that the overwhelming majority—well over 99%—of US high schools offer some kind of sports program.