I usually find leaf skeletons in the spring, after months of rain and snow has mouldered away the tender parts, leaving the vascular tissue (the "bones"). But sometimes I find the occasional leaf turning to skeleton before leaving home - helped along by fungi, I'm sure.
This week, head outside and look for leaf skeletons. If you don't want to wait around for spring, you can make your own. It is fun for kids, but adult supervision is needed. Here's how.