The original junior high in West Des Moines was called Valley Junior High and was located at 7th and Hillside, just east of the old Valley High. In the late 1950's the school district made plans to build a larger junior high.

Stilwell Junior High opened its doors in the fall of 1960. Stilwell was named after Mr. Elbert I. Stilwell, President of the West Des Moines Board of Education. Mrs. Harriette Knapp, the first principal, was followed by Mr. Dick Snell, Mr. Jim Stone, Mr. Tom Drake, and Mr. Les Aasheim. Mr. Tim Miller is the current principal.

The original Stilwell building consisted of the west two-story wing and the middle wing which contained a multipurpose room that is now an art room and a drama room. The old multipurpose room was used for P.E., music, band and lunch. There was no hot lunch program.

In 1962, the second stage of construction, the gym, stage, locker room, art and technology education rooms were added. At that time, an open patio area was located where the present lunchroom and library now exist.

In 1987 - 88 construction enlarged the library, added a multipurpose room, and remodeled the family consumer science facilities. Additionally, the office area was enlarged and remodeled.

Construction of the newest addition to Stilwell started during the summer of 1991 and continued through the summer and into the fall of 1992. The 1992-93 school year was the first year of usage for the new two-story classroom wing on the north side of the building.

Also, the gymnasium , multipurpose room, and music facility were used for the first time 1992-93. This addition is on the east side of the building and ties into the initial structure. The food service area has undergone both addition and renovation.

The entire north side of the original building has been remodeled. The media center has expanded into the old multipurpose room and an adjacent classroom. The old gym is now an auditorium.

The second story of the original two-story classroom area has been carpeted and new windows installed. The first floor has been redone so the main entry is on the west side of the building. The office has been expanded to include the area from the previous office to the new entryway.

In 2003 a remodeling project was completed which provided air conditioning to areas of the building that had been without it. A new mechanical room was added to the northeast corner of the building. The two science rooms on the west side of the building were expanded and updated.