24 Creepy Halloween Birthday Party Ideas

Spiders bursting out of a sac sounds horrifying to us, but at this time of year scary is superb—especially for kids. We're happy to report that despite their name, once submerged in water, each of the green sacs bursts forth a multitude of balls, not spiders (some 100 times the original size). These can then be bounced, rolled, thrown and squished.