DINO DIG

The last class in this month's series is Paleontology. The word fossil means "dug up". A fossil is the remains of any living organism. A paleontologist studies fossils and can specialize in different areas. Today's class will specialize in dinosaur fossils. I began with a book "BOY WERE WE WRONG". I sat the kids on the floor in a circle and brought out a plastic Stegosaurus and pretended that it was walking through the grasslands and it was older so it died. I asked them if they thought that it would become fossilized. Most kids said that it would. I then brought out a toy Allosaurus. I then acted out that the Allosaurus eating the Stegosaurus. For a dinosaur to become fossilized it had to become hidden from the predators. I had the students guess what could hide them. Sand storms, rock slides, quick sand, and floods were the favorite answers. Once the dinosaur was buried I asked which parts would become fossilized. The hard parts like the bones, spikes, teeth, and claws were what most kids think of. I added that skin prints, eggs, poops and footprints could be left behind too. I then moved on to showing the children the 2 groups of fossils. The first type is a replacement fossil. These are usually teeth, caws, bones, poops and eggs. The bone has tiny holes all over it and it lies in the dirt, water washes in and pushes a little of the bone out. Luckily it leaves a little piece of mineral in its place. I then passed around a T. Rex tooth replica. The second type is mold and cast which is footprints and skin prints. We pushed dinos into modeling clay to see the impressions left behind.

Next we went through what it would be like to work on a dig. First we'd go out west to Colorado, Utah or South Dakota where there are more dino remains than here in North Carolina. Then when we began to dig we'd photograph the cite, map the cite and as each fossil is removed we number it and mark the number on the map. The bones are wrapped in plaster wrap and transported to the museum or university to be cleaned, studied and reassembled. After digging a small T. Rex skeleton out of sand each student wrapped their bone with toilet paper and loaded into the back of a toy dump truck. We then drove the skeleton to the museum. Each child took a fossil package out and unwrapped it and we reassembled the skeleton.

DINO WARS

T.Rex is by far the most famous dinosaur and kids love how huge and dangerous they were. This weeks class was called DINO WARS and I started the class with a book called DINO DINNER and as we read it I talked about carnivores (meat eaters), herbivores (plant eaters), and omnivores (eats both). We then did and experiment to see how the large sauropods (brachisaurus et al) ate and survived. I explained that they were so large that they had to eat all day to stay alive. Many of the trees were evergreens and I had them think about eating a Christmas Tree. The leaves were tough and these animals didn't have time to chew, so they used a gizzard. I had a Tupperware container with a great fitting lid. I put a lettuce leaf in it torn into very large pieces and put the top on and we passed it around and each child shook it, pretending that it was a dino stomach. When I dumped it at the end they could see their was no change to the leaves. I then explained that these dinos swallowed rocks that went into a separate stomach called a gizzard. I then put the leaves back in with the rocks and we passed it around again. Make sure the top won't come off here and send rocks flying. When we dumped it this time you could see they looked like they had been chewed. After several months the rocks would get polished and not work as well so the dinosaur would have to spit them up and swallow new rough ones. I then brought out a potato masher, spatula, bread knife and golf tee. I named a dinosaur and had the kids guess which utensil would be most like their teeth. Parasoralophus and other duck bills would have grinding teeth like the potato masher. Mamenchisaurus would have teeth like spatulas to shovel in leaves. Spinosaurus had teeth like the knife. Baryonx had claws to catch fish with like the gold tee. Then I had Swedish Fish and let each child stab a fish with the golf tee (their claw) and eat them.

The book DINO WARS has a point system for each dinosaur. The largest number wins. I had cards with dino pictures on them. Two children would throw down a card and we check points to see who would win. We ended with a tie between T. Rex and Gigantasaurus. I then thew down an asteroid who scientists think defeated them all.

National Geographic has a great website filled with bizare dinosaurs and we looked at some of these.

http://ngm.nationalgeographic.com/2007/12/bizarre-dinosaurs/dinosaur-interactive

Our project was a small dinosaur world made inside of a plastic ball that I ordered from Discount School Supplies. We used model magic for dirt, volcanoes, lava, and water. Fake plants made the trees and 2 tiny T. Rex figurines went inside. We carry these at Science Safari.

DINOSAURS

I enjoy teaching dinosaurs because the children are so interested in them. There will be one student in most classes that know almost every dinosaur. The majority of the kids only know T. Rex, Triceratops, Stegosaurus, and they call Apatasaurus a long neck. Most information that younger children get are from "Land Before Time" movies.

I begin with what is and isn't a dinosaur. Not all reptiles that lived in the Mesozoic Age are dinosaurs. Dinosaurs did not have flippers and live their entire life in the water. Dinosaurs could swim however. Elasmosaurs and others were not dinos. Dinosaurs could not just fly with wings. Pterosaurs weren't dinos. Some of the later dinos had feathers and could glide or fly but could also fly. Dinosaurs had legs that came down straight not bent like those of a crocodile today. I had toy models so the children could chose who was and was not a dinosaur. You could do this with pictures too.

We then played "Name That Dinosaur". I had toy models and placed one in the child's hands, but there hands were behind their back and they guessed which it was by feeling for horns, spikes and claws. The kids love playing and when we were done we sorted them by herbivores and carnivores. Al herbivore dinosaurs walked on 4 legs. Not all dinosaurs that walked on 2 legs were carnivores. You must look at their head and teeth to decide. We then sorted them by the time period they lived in. The Triassic was first and we saw a Plateosaurus. The Jurassic was the time of the large herbivores. The Cretaceous had the largest meat eaters.

We then looked at my Iguana, Ozzy and talked about his difference and similarities to a dinosaur. His legs are bent which make him not a dino. His spines on the back are similar, his tail can whip like a sauropods tail. He's covered in spines.

We then created our own dinosaurs out of clay. I explained that no one knows what colors dinosaurs were because we have no color left behind in fossils. They could make them any colors that they wanted to.

Reptiles - Jan 2010

I began the year with my favorite topic - Reptiles. I usually begin class with a book and this week I used CAN SNAKES CRAWL BACKWARDS. I began with talking about animal classifications.

Vertebrates - have a skeleton
Invertebrates - no skeleton

The 5 main classes of vertebrates are Mammals, Birds, Reptiles, Amphibians and Fish.
There are 5 orders of groups of reptiles living on earth today:

Tuataras, Snakes, Lizards, Crocodilians, Turtles

There are many types of extinct reptiles.

I then went over the characteristics that make a reptile a reptile:

1. Scales - I asked the kids to show me there scales. They of course responded that they had no scales and I pointed to there fingernails and hair. They are made of keratin which is the same material reptile scales are made of. Why are the scales so important? I explained that if I made a sandwich for their lunch early in the morning and left it laying in the desk all day that my lunch it would be dry and stale and not very good. I asked what I should do with the sandwich to make it better for lunch and most kids know you should put it in a zip lock. Think of scales like a zip lock. They keep reptiles from drying up and allows them to live in saltwater and hot, dry desserts that the amphibians with no scales can't live in. The scales also protect their bellies. I asked the kids if they would like to crawl through the park on their bellies in a bathing suit. If they had scales they could.

You can cut the end off of a pillow case and put it over a child and let them lay down and try to shed their old scales off. Remind them that if they were a snake they'd have no arms to help with. Real snakes don't just crawl out of their skin but they peel it off like a banana skin.



2. Breath with lungs - Reptiles do not have gills so, sharks are not reptiles even though they have scales.

3. Body Temp - Reptiles are cold blooded, we are mammals and are warm blooded. We can make heat to maintain a steady temp. If we go out to play in the snow we don't die. Reptiles do not have ice in there blood but they can't make heat (except a few pythons when protecting eggs). If a lizard goes out in the snow it will die. Even if you put a coat, hat and gloves on it. That's why they hibernate in winter or live in warm places.

4. Reptiles lay eggs with shells.

I then gave everyone a toy reptile, amphibian, fish and eel. I said crocodilian and everyone with a croc or alligator put it in line,snakes, turtles and lizards. We talked about why the salamander wasn't a reptile (no scales and only 4 toes on the front legs). You could do this with pictures too.

I have 2 live snakes we looked at, ask around the school many kids have pet snakes or lizards they'd love to bring in to share. Make sure it's friendly before allowing anyone to touch it.

Our project for the week was making a snake scarf. We made a nonvenomous constrictor. I had explained when holding the snake that I never hold one around my neck because when a constrictor gets scared it could squeeze. The scarf we're making is ok for the neck. I cut the snakes out of fleece ( I got about 7 snakes per yard). You could get more by making them little shorter and skinnier. We then glued on eyes cut out of white felt, forked tongues of red felt and we glued in elliptical pupils of black felt. Our pythons are nocturnal and need eyes to open wide at night. My older students added the nostrils and heat seeking pits with a black sharpy.