Way back when I was in college, I spent a summer working as a cave guide in Sequoia National Park. We wore funny green berets that made everyone comment on how we looked more like, well, Green Berets, than park interpreters. I lived in Lodgepole with a bunch of friends and went caving and backpacking on my days off. Pretty much a dream job.
That summer ignited my love for caves. The following summer I went to West Virginia to take teens caving, backpacking, and mountain biking. It cemented my interest in crawling around in the dirt underground. There are tight squeezes (places you have to exhale to fit through), low ceilings, and exposed climbs, and then you pop into a room filled with decorations. Stalactites, soda straws, cave bacon, and stalagmites reflect in your headlamp like a diamond chandelier.
So, I like caves.
We are spending a couple weeks at the beginning of this no-school year studying the biology and geology of caves.
Videos
I have a big ol’ science crush on Bill Nye the Science Guy, so whenever I can work one of his 1980s kids’ videos into our day, I do.
[video:youtube:m8InLteUI40]I’m sure you watched all 23 minutes of this video and loved it.
Build a Cave
Next up was cave building.
We stacked sugar cubes and covered them with clay. The sugar cubes represented limestone (a soft material that is worn away by water), and the clay is the harder rock overlying the limestone. We made sure at least part of a sugar cube stuck out.
We let the mountains dry out for a day or two and then sprayed water in the holes, on the sugar cubes. As you can imagine, the sugar cubes dissolved and our mountain became a cave. Just as the limestone is worn away by water, forming real caves.
Grow Stalactites
Once you have a cave, you need some decorations. We followed Bill Nye’s advice (remember, from the video?) and grew stalactites. We cut a hole in the top of a box (our cave) and inserted a cup. Then we tied pieces of yarn to metal nuts to hold them down in the cup. We poked a few holes in the top of the cave and threaded the yarn through it, so they hung down from the ceiling of the cave.
We mixed as much Epson salt into hot water as the water would hold, then poured it into the cup after it had cooled a little. A little time, a little capillary action, and we had stalactites.
Field Trip
We haven’t done this part, yet. Now that we know all sorts of things about caves, it is time to explore one. This weekend, We will take a family trip to Lewis and Clark Caverns State Park.
I took the tour a bunch of times with teens when I worked for Montana Outdoor Science School. It’s kind of cheesy with the guides pointing out the “wedding cake” and the formation that looks like Romeo and Juliet. I know I am a cave snob, but I want more geology and less silly names. I can decide for myself what things look like.
That said, I’m excited for the boys to walk around in the cave after all the reading, watching, and building they’ve been doing. We visited Jewel Cave a couple years ago, but don’t the boys don’t really remember it. I just hope they can go two hours without having to pee.
UPDATE: We made it to Lewis and Clark Caverns!
Books
We can’t fully cover a subject without books. We love reading.
Caves and Caverns by Gail Gibbons
Cave by Donald Silver and Patricia Wynne
Caves: Mysteries Beneath Our Feet by David L. Harrison
Bats by Gail Gibbons (can you tell we are fans?)
Bats (Lerner Natural Science Books) by Sylvia A. Johnson
I bet you were the greatest guide ever! The unit looks like so much fun!
Jen E. – There was one guide who was even better, but she was very tiny.
I know two boys in SoCal who would love to explore caves with you!
I know two boys in So Cal that I’d love to take caving, Debi (and their mom!).