From the plaque:
Altaville Grammar School
This brick building, erected
in 1858 with funds raised by a dance in the Billiard Saloon
of the N.R. Prince Building (which still stands, 1955)
is one of the oldest schools of California. It was in
use until 1950, when it was replaced by the present Mark Twain
Elementary School in Altaville.
Marker placed by the California State Park Commission in cooperation with Princess Parlor No. 84, Native Daughters of the Golden West, May 1, 1955.