These will blow the mind of a child on Easter morning and is a fun afternoon project. I made these for a video I shot. We needed large eggs that I could put a hand inside and break out of, and these worked nicely. But I also found that they were fun to make, great decorations and kids love them. Thanks to Tom Cline for showing me his Giant Plaster Egg 12 years ago.
WARNING, this is easy to do, but tough to master. It will take several attempts. Be patient and do this in an area you don't mind getting dirty. The eggs tend to explode when you are making them, (nothing dangerous, but messy) and you will get plaster everywhere.
Step 1: Materials
Plaster of Paris-one box.
Bag of 9" balloons-round (but really Egg Shaped) clear is best, or white or yellow, easy to see through.
Empty bottles of water-1/2 liter. Easy to crush.
Mixing cup, more than 1/2 liter.
Exacto Knife or Razor Blade
Towels, drop cloth, (did I mention this is messy?)