A 2004 Texas Historical Marker provides some background:
Thornton was established in 1871 by the Texas Central Railroad and had a post office by 1873. By 1880, the town had approximately 200 residents and three churches, as well as several businesses and a Masonic lodge. Early schools included the Thornton Male and Female Institute, founded in 1877 by physician and teacher Edward Coke Chambers.
The Institute, known also as Thornton College, included a wood-frame classroom building, student housing and Chambers' home. The school received its charter in 1881 and in 1884 merged with the school of Henry P. Davis. In 1889, Chambers sold the Institute to Davis, who continued to operate the school until 1891, when he sold it to the newly formed Thornton Independent School District.
In 1903, a storm destroyed the school building, and in 1920, the second school building burned. The third schoolhouse, built of brick, was completed in 1921.
During the 1930s and 1940s, several rural districts consolidated with Thornton, including all or part of Mill Creek, Prairie View, Pleasant Grove, Davis Prairie, Beulah and Eutaw Springs common school districts. In the early 1960s, with a declining student population, Thornton began to close its schools. African American students, who had for many years attended a Rosenwald School on Ellis Street, began traveling to Groesbeck for classes, as did the high school students from the White campus.
In 1965, Thornton consolidated completely with the Groesbeck Independent School District, stipulating in the transfer that the main school building and grounds at this site be deeded to the city for use as a community center.
The Place:
An article in the March 29, 2018 Groesbeck Journal noted that the old school building had been demolished about five years previously -- there's no explanation as to how or why the façade survived -- but there was still hope that the property could be used as intended. Mary Helen (Nance) Campbell and her husband came to the rescue, covering either all of the costs, as she had been a student at the old school and wanted to give something back to the community that had nurtured her. What stands here now is a multipurpose event venue with a kitchen, dining hall, and meeting room, and reservations can be made through the City of Thornton at 254-380-1139. At front and center are bricks from the old school, along with the entry arch, the support columns, and the "Thornton School" frieze.
The Person:
A more recent article (April 22, 2021) in the same newspaper covered Mrs. (Nance) Campbell's 100th birthday, and it tells a little bit about her:
MARY HELEN NANCE CAMPBELL CELEBRATES 100 BIRTHDAY
April 12, 2021 – Wow what a day! Mary Helen wanted to come "home" to celebrate her 100th Birthday. She was born to Bertha and Louie Nance on April 12, 1921, about 1 1/2 miles south of Thornton. The area Nances gathered at the home place of Mary Helen to celebrate her 100th Birthday. The home and land have been in the Nance family since 1872 and is still owned by the family. As far as our records show, Mary Helen is the first Nance to reach 100 years old. Mary Helen graduated from Thornton High School in 1938 and then attended the University of Texas. Mary Helen loves her family and has proved it in many ways. Also, she has always been proud of her town and county. She has shown this by her donations to the Limestone Medical Center, Groesbeck, and for the building of the Community Center in Thornton. It was a blessed day to be with her and her husband, Bailey Campbell, wishing her well and many more years.
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A 2013 Street View on Google Maps has a look at the old school before its demolition.