The name ‘Sumner’ comes from the former name of Helensview School at NE 87th and NE Sumner. It used to be Sumner Elementary school in the Parkrose School District.
The abbreviation ‘SAN’ was selected because the old-timers in the neighborhood referred to the field next to I-205 (along NE 92nd Ave north of NE Sandy Blvd) as the “sandlot” — their pronunciation dropping the ‘d’. (Before the I-205 freeway was completed in 1976, the SAN lot was the Sandy Blvd Drive-In movie theater.)