When I was in elementary school, my mother decided to winterize the windows of our house. It was already a rather dark and cave-like environment because of the poorly placed lighting and the cheap brown wood paneling that covered most of the walls, but the winterizing would also block all sources of sunlight. My mother took large slabs of styrofoam cut to fit each window and covered the windows with them. They covered every window in the house that wasn't already obscured by the hoard. Then she covered the windows with that clear cling wrap material and vacuum sealed it to the windows. It was years before any of it got taken down.
On the bright side, the sliding glass door at the back of the house had come off its track and didn't close all the way anymore, and the styrofoam was the only thing blocking the cold.