I think I've found your artist.
The Gilbert School, Winsted CT (photo 1)
Watercolor of the same school, by alumni Gloria B. Youmatz (photo 2)
I'm thinking the 'B' is either a typo or represents her maiden name.
http://articles.courant.com/keyword/wilbraham/featured/3"Youmatz, Gloria T. (blasette)
March 6, 2005
YOUMATZ, Gloria T. (Blasette) Gloria T. (Blasette) Youmatz, 81, of Brookmont Drive, Wilbraham, MA died Thursday, (March 3, 2005) at the Heritage Hall Hospice Unit in Agawam, MA.
Born in Winsted, February 26, 1924, she was the daughter of the late Flavian and Jeanette (Bruno) Blasette. Gloria was a
resident of Wilbraham for 33 years, having moved there from Winsted in 1972. She was a dental hygienist for many years, working for several dentists including Dr. Neville Sweeney of Winsted and Dr. Carl Brigada of Springfield."
http://www.genealogybank.com/gbnk/obituaries/?p_field_base-0=gblname&action=search&p_text_base-0=Youmatz&kbid=5747&s_referrer=daddezio02&Mrs. Gloria T. Youmatz Was dental hygienist, artist
Date:Sunday, March 6, 2005
Location:Connecticut
Paper:Republican-American (Waterbury, CT)
Haven't really found anything else by her (yet).