From left, Dolores Thompson, also known as “Grandma Dee” and Nicole Seeley, a third-grade teacher at Harvey C. Fenner Elementary School, stand near a poster that breaks down 90 years into months, weeks, days, hours, minuters, and seconds. The poster is part of the timeline that led up to Thompson’s 90th birthday. P-J photo by Michael Zabrodsky

FALCONER — For Delores Thompson, being a volunteer at Harvey C. Fenner Elementary School is icing on the cake — literally and figuratively.

On Tuesday, “Grandma Dee” as she is affectionately known, celebrated her 90th birthday within Nicole Seeley’s third-grade class.

Since 2012, Thompson has been part of the AmeriCorps Senior Foster Grandparent Program, and she volunteers three days per week and five hours per day at Fenner.