Born in Boston, Massachusetts, in 1925, Kay attended the Museum of Fine Arts from 1941-1943 when he stopped to serve in armed forces in Europe during World War II. Returning to the Museum School on the GI bill, in 1946, he graduated in 1949 with a prestigious James William Paige Traveling Fellowship to continue his studies in Europe. Upon return to the United States, in 1951, he taught at the Museum School until 1955 before joining former classmate David Aronson and others in helping to establish a studio art program at Boston University, where he taught from 1956 until his retirement as Professor Emeritus in 1989.
Author of numerous books on painting technique, Kay has conducted workshops in painting methods and materials at various colleges and institutions throughout the United States. In 1981, he received an Artist Fellowship grant from the National Endowment for the Arts and was elected to the National Academy of Design, New York, NYC, 2003. His work is in the permanent collections of numerous museums, including the Cape Ann Museum, Gloucester, MA; Danforth Art, Framingham, MA; the deCordova Sculpture Park and Museum, Lincoln, MA; the National Academy Museum, NYC; and the Rose Art Museum at Brandeis University, Waltham, MA. The artist is currently represented by Alpha Gallery, Boston. He lives and works at his home in Brookline, Massachusetts.