I'm so bad at math I have to count the dots on the dice to play Yahtzee, and nobody wants to play Cribbage with me because I have such a hard time finding the 15s and doing the counts. <Sigh> Not a whole lot upstairs, but from there on down, Disneyland!

Love it. I'm right there with ya on math skills!
Measure the opening of the nest box. Cut two pieces of fabric to about the width of half the opening and hem the edges of the fabric. Attach the curtains to the outside of the nest box with staples or Velcro fasteners. Attach a piece of ribbon to either side of the opening and tie the curtains open with the ribbons