The district was established on February 26, 1953 after the mergers of the schools of Hattersville, Long Creek, New Hope, and Tripp.
Although the entire district was located in one building, construction began on a new high school for students in grades 5-8. Construction had been completed for the 2006–2007 school year.
The residents of SISD approved a bond to build a high school. Sunnyvale High School was housed at the middle school campus prior to its campus's opening in the fall of 2009. As of August 24, 2009, the Sunnyvale High School opened its doors to students.
In 2011, the town of Sunnyvale approved a $16.8 million bond election for the construction of a new elementary school to replace their current 50-year-old one. The bond election raised taxes on evaluations 7¢ per $100. The bond was approved and the school was completed in time for the 2012–2013 school year.
- Sunnyvale High School
- Sunnyvale Middle School
- Sunnyvale Intermediate school
- Sunnyvale Elementary School
In 1997 96.1% of the students were non-Hispanic white. By 2016 the percentage declined to a point slightly above 50%, although the actual number of non-Hispanic white students had increased, contrasting with the white flight seen in other Dallas County school districts. In 2016 13.3% of the students were classified as economically disadvantaged, an increase from past figures.
- "History of Sunnyvale Schools". Sunnyvale Independent School District. 2007-10-30. Archived from the original on 2007-10-30. Retrieved 2019-10-30.
- Korosec, Thomas (March 2012). "Sunnyvale: The Whitest Town in North Texas". D Magazine. Retrieved 2019-10-30.
- Anderson, Karin Shaw Sunnyvale looking to heal: Planning under way for new school that divided residents before vote, Dallas Morning News, 2007-05-18
- Simnacher, Joe, After 56 years, Sunnyvale's first high school opens this month, Dallas Morning News, 2009-08-09
- "2009 Accountability Rating System". Texas Education Agency. Archived from the original on 2015-10-25.
- "Mayor's race, school bond ensure active election season in Sunnyvale | Dallas-Fort Worth Communities - News for Dallas, Texas - The Dallas Morning News". Archived from the original on 2011-03-21.
- Nicholson, Eric (2016-05-03). "In Dallas, White Flight Never Ends". Dallas Observer. Retrieved 2019-10-29.
Like Sunnyvale, it's [sic] white population has increased. Unlike Sunnyvale, its low-income population has not.