The League's One-Act Play Contest, founded in 1927, is the largest high school play production contest or play festival in the world. More than 14,000 Texas high school students in more than 1,000 plays participate in 300 plus contests, which take place from the beginning of March through the three-day, 40-production State Meet One-Act Play Contest. The One-Act Play Contest is supported by more than 200 college and university faculty members serving as critic judges. The League's theatre program is considered by historians to be the foundation of educational and community theatre in Texas. It continues to be a major factor motivating increasing numbers of schools to offer theatre arts as an academic subject.
The UIL One-Act Play contest is a competition where similarly sized Texas schools present an 18-40 minute play usually adjudicated by a single judge. The contest is held on a single day and open to the public. There are five possible levels of competition: Zone, District, Area, Region, and State. At each level of competition the judge awards individual acting awards as well as selecting two productions to advance to the next level of competition. After the awards are announced the Judge gives an oral critique to each of the schools. Because of the wide participation and diversity of plays produced certain rules and guidelines have been adopted by the State One-Act Play Office. These rules are in place to ensure safety, allow for equity, satisfy legal standards, and make the running of the contest practical.