Alissa was last seen at her residence around 10 p.m. Tuesday in the 4300 block of Germantown Avenue.
She attends Edward T. Steel Elementary School in the 4300 block of Wayne Avenue.
Alissa is described as 4 feet 9 inches tall, 112 pounds with brown eyes, thin build, medium-brown complexion and curly, black shoulder-length hair.
She was last seen wearing a red shirt and blue pants.
Anyone with information on Alissa's whereabouts is asked to call police at 215-686-3353 or 911.