The characters gazed up at the impressive mansion looming over them. Its grandeur was evident, as the large square structure commanded attention with its pristine white exterior. This striking house served as a focal point for the unfolding mystery, intriguing the characters and drawing them closer to their exploration.

The description of the mansion not only highlights its size and color but also sets the stage for the adventures that await within its walls. The anticipation of discovering what secrets the house holds adds to the suspense of the story, making it an integral part of the plot in "Schoolhouse Mystery" by Gertrude Chandler Warner.