Alta Zimmerman Peterson, 90, a retired guidance counselor and English teacher at Springfield High School in Delaware County, died of a stroke Oct. 1 at Dunwoody Village in Newtown Square.

A native of Lancaster County, Mrs. Peterson earned a bachelor's degree from Millersville State College and a master's degree in education from Pennsylvania State University. She taught for 11 years in Lancaster County schools before marrying Cecil E. Peterson, an architectural engineer, in 1948.

The couple moved to Delaware County in 1953. The next year, Mrs. Peterson began teaching in the Springfield Township School District; she joined the high school faculty in 1959.

She was a counselor at the high school for a number of years but returned to teaching for 10 years, before retiring in 1984, because she felt she could help more children in the classroom, said her daughter, Anne. She shared her appreciation of literature and poetry with her students, her daughter said.

An eclectic bibliophile, Mrs. Peterson recently read Milton's Paradise Lost and had been reading The Diary of Samuel Pepys. She often exchanged books by contemporary authors with her daughter, including Bel Canto by Ann Patchett and The Kite Runner by Khaled Hosseini. She enjoyed word puzzles and gardening.

In addition to her daughter, Mrs. Peterson is survived by a son, Michael; a daughter, Meg; a sister; and six grandchildren. Her husband died in 2000.

She donated her body to science and there were no services.

Donations may be made to the Cecil Peterson Memorial Fund, St. Matthew Lutheran Church, 400 Lynbrooke Rd., Springfield, Pa. 19064. Mrs. Peterson had been an active member of the church.