Above is the second school built in Pittsburg, and was located near the corner of Tenth and Broadway. It was an eight-room brick structure that cost $12,000 to build. It had one room devoted to high school curriculum while the other rooms were used for other grades. The first senior class graduated in 1888 with six students. The building was torn down in 1888 and was replaced with a larger twelve-room brick structure, that opened in 1889, that became known as the Granby School. That first year there was no graduating class. The next year, 1890, saw only one student graduate. The Granby School was closed and torn down about 1903 when the new Senior High School was built at 807 N. Broadway.

Senior High School - 807 N. Broadway
- postmarked 1907

Senior High School - 807 N. Broadway
- no postmark (c1907 - 1914)

High School Building- 807 N. Broadway
- postmarked 1908

Senior High School - 807 N. Broadway
- Postmarked 1910

Senior High School - 807 N. Broadway
Image from 4 School Postcard - postmarked 1912

Senior High School - 807 N. Broadway
- photo Prosperous Pittsburg, Pictorially Portrayed - 1915

This Senior High School building, located at 807 N. Broadway was built in 1903 at a cost of $35,000. It was used as the high school until 1921 when the building at 1310 N. Broadway was built. After the high school moved out, the building became the Roosevelt Junior High and was used in that capacity until 1939 when an addition was added to the high school and Roosevelt Junior High was moved there. This building was torn down in about 1940.

Senior High School - 1310 N. Broadway
- no postmark (1915 - 1930)

This Senior High School, designed by William J. Schmitt & Hawk & Parr of Oklahoma City, OK, was built in 1921. A three-story addition was added to the back of the building in 1939 and Roosevelt Junior High was moved there. In 1979, a new high school building was built at 1978 E. Fourth and this building became Pittsburg Middle School, consolidation of Roosevelt Junior High and Lakeside Junior High Schools, with grades 6 - 8. Another three-story addition was added to the back of the 1939 addition in 2004.