Seishou Elementary School (私立聖祥大学付属小学校 Seishō Daigaku Fuzoku Shōgakkō, lit. "Seishou University-affiliated Elementary School") is a three-year elementary school in Uminari City, attended by Nanoha Takamachi, Alisa Bannings, and Suzuka Tsukimura in the original series. Unlike the Seishou Junior High School, it seems to be co-ed.
In A's and A's manga, Fate Testarossa enrolls in Seishou Elementary School, as well. It is mentioned that had Hayate Yagami not suffered from a debilitating decease, she would have attended it, too.
The Seishou Elementary School schoolgirl uniform was the prototype of Nanoha's original Barrier Jacket, some elements of which are retained in all later versions of it.
Male and female school uniforms