This week we've started a dinosaur mini unit. Dinosaurs are great for unit studies because there is so much material available! We actually started when the Adventurers saw the dinosaurs a section of the Natural History Museum.
One thing we did was draw a life sized head of a young Tyrannosaur. We put it at the top of the stairs because that's about where his head would be if he were standing at the bottom.
Would you dare turn on the light?
We've been using "fun sheets" and printables from Learning Page. If you haven't seen this site, it's amazing! Plus, it's free! For the subject of dinosaurs alone, they have about 60 worksheets per grade divided into math, language arts, and science. That's not even looking at their "fact files," teaching tips, and murals. The only down side is that they only go from kindergarten to grade 3.
All my kids have enjoyed their stuff, but Choclo went crazy for the kindergarten sheets. He kept begging me to print more! He probably did 20 of them before we ran out of time.
We also did a mural. Mxyl did the background and everyone colored and cut out dinosaurs from a coloring book I had on hand. This was fun because the kids all had stories about what each dinosaur was doing and how it died...
We had our biggest dino day on Friday. We had some friends over and did a ton of dino stuff.
We looked at examples of fossil impressions and casts, then made our own with play dough and plaster of paris. If I had to do it again, after they make the impression in the dough, I would have sprayed it with cooking spray. As it was, the dough absorbed some of the water from the plaster and got sticky and hard to wipe off. The casts still came out well. The one in the picture is a trilobite cast.
We also looked at how fossils are formed by cutting out bone shaped sponges and soaking them in super salty water. As they dry, the holes in the sponge fill up with salt crystals and turn the "bone" hard. In real fossils, of course, the holes are smaller and they fill with other minerals, but these have the advantage of being done in a few days!
The favorite activity, however, was chipping bones out of plaster "rocks" that I had prepared. The idea was to chip them out carefully with a screwdriver chisel and a hammer, but, really, is there anything more satisfying to a 5 year old boy than pounding plaster to dust with a hammer?
We've also been watching the "Walking with Dinosaurs" series. This has been really interesting. Some of it is obviously guesswork (the allosaurs showing maturity by getting red eye crests), but most of it is based on the fossil record.
My favorite part has really been the way it shows which dinosaurs lived together and what their world was like at the time. The "prequel" Walking with Monsters was especially good, as it showed how the atmosphere and temperature of the Earth changed and allowed different kinds of animals to exist.
For example, because the plants made it to land before the animals, the oxygen levels rose far above current levels, allowing the development of giant insects. Because insects don't have lungs (they have holes called spiracles that allow oxygen to diffuse directly into their circulatory system) those giant dragonflies would suffocate in today's atmosphere. There simply wouldn't be enough oxygen to support a three foot insect (and I can't say I'm sad about that).
The down side to the series is that it's a bit gory. This hasn't bothered the kids at all. But I had to wonder when the allosaurs brought down the diplodicus and Klenda helpfully urged them, "Rip open its soft underbelly!"
We also took our first trip to Dinosaur Park! It's a very rich fossil dig that's open to the public twice a month. The bad news: any fossils you find belong to the state. The good news: they don't care about lignite (tree fossils the stage before coal). We didn't actually find anything but lignite, but we found several nice large pieces of it that we were allowed to take home. We only stayed about an hour because our hands were turning blue, but I think we'll do it again in warmer weather!