R. C. Clark High School is a co-educational secondary school in Plano, Texas (USA) serving grades nine and ten. Founded in 1979, the school is part of the Plano Independent School District. Hendrick Middle School, Carpenter Middle School, and Schimelpfenig Middle School feed into Clark. Students leaving Clark go on to attend Plano Senior High School. The school colors are red, white, and black, and the school mascot is the Wildcats.

The high school added a new wing to the building for the 2012-2013 school year due to overcrowding in the old building. The new building houses science, art, and foreign language classes.

Clark High School is named in honor of Richard Calhoun Clark, a pioneer, and farmer who served in the Civil War under General R.W. Carpenter after the death of his father.

Previously, only Carpenter and Hendrick Middle Schools fed into Clark High School and were zoned to Plano East Senior High until 2011-2012. In the 2011-2012 school year, Schimelpfenig students got to choose whether to go to Clark or Jasper High School. In the 2012-2013 school year, after school population debate, Schimelpfenig was zoned only to Clark High School.

Clark High School currently offers 3 AP courses: AP Human Geography, AP World History, and AP European History. Additionally, starting in the 2017-2018 school year, Clark will also offer AP Fundamentals of Computer Science. Students may also take AP Statistics at Plano Senior High School if they have completed all prior math courses. If there are enough students registered for the course, Clark High School will offer AP Calculus AB or BC; otherwise, students may take the course at Plano Senior High School. Clark also offers a variety of honors, regulars, and extracurricular courses along with many sports. Student athletes may choose to play for the Plano Senior High School teams.

• 1992–93 National Blue Ribbon School