Her husband said that Mrs. Laster helped develop her school's part in other artistic programs in the 1990s.
In 1997, she won a William Ross Award for Teaching.
Born in Valley Forge, Mrs. Laster graduated from Clifton Heights High School in 1969. She earned a bachelor's degree in elementary education in 1974 and a master's in educational research in 1984, both from what is now West Chester University.
She took graduate courses at several colleges and universities, her husband said, and began her career as a teacher and tutor at Henderson High School in West Chester in the 1974-75 academic year.
In 1976-76, she taught mathematics at what is now the Dimner Beeber Middle School in Overbrook and won a merit award for her teaching there, her husband said.
She taught third grade at Harrington Elementary School in 1977-78 and fifth and sixth grades at Samuel Powel Elementary School in 1978-79, both in West Philadelphia.
Mrs. Laster then shifted her focus.
After working with the Women Against Abuse Center from 1979 to 1981, she was an administrative assistant at the Women's Center at West Chester University in 1983-84.
Mrs. Laster was math department chair from 1984 to 1987 for St. Gabriel's Hall, which describes itself as "a residential program for young men ages 10 to 18 adjudicated by the Philadelphia court system."
Mrs. Laster returned to the classroom as a special-education teacher in Lower Merion, Upper Merion, and Erdenheim until 1989. She then taught seventh grade at John P. Turner School until 1993.
She earned scholarships to summer courses, such as one on nuclear science in 1999 and one on meteorology in 2002.
Mrs. Laster was a delegate to the 1972 Democratic National Convention, her husband said, and in Wayne she was a Democratic elections official for more than 20 years.
Besides her husband of 39 years, Mrs. Laster is survived by her father, Thomas J. Stearns Jr.; a son, Jeremy; daughters Emily, Lori, and Amy Poe; and two brothers.
A memorial service was scheduled for 1 p.m. Sunday, Aug. 19, at Joseph Levine & Son, 2811 West Chester Pike, Broomall.
Contact Walter F. Naedele at 215-854-5607 or firstname.lastname@example.org.