backpack mail
n.— «The dispute started last summer when Gabriel and Joshua Rakoski, twins who attend Hollymead Elementary School, sought permission to distribute fliers about their church’s Vacation Bible School to their peers via “backpack mail.” Many public schools use special folders placed in student backpacks to distribute notices about schools events and sometimes extra-curricular activities to parents.» —“Falwell’s Flub: Jerry-Rigged Policy Opens Door For Pagan Proselytizing In Virginia Public School” by Rob Boston The Wall of Separation Dec. 5, 2006. (source: Double-Tongued Dictionary)