The first penny toss was held in December 1924. This quote comes from a letter written by the Sisters of the Rosemont Community.
"On the night before the students left they assembled before the front door and, carrying red candles, sang carols all around the house. When they reached the porch Reverend Mother (M.M. Ignatius) went out to them and threw pennies, for which they scrambled in true Christmas wait fashion."
"Wait" in this case is a term for street carolers. In England it was common to give food or coins to visiting carolers as they went door to door and it seems that the Sisters put their own twists on this tradition.
The Penny Toss has been held every year since that first event in 1924 making it the College's oldest (and most beloved) tradition.