On our last dinosaur week, we explored the ancient oceans and the animals that once lived there.
Lesson Time: Just as the flying dinosaurs were not really dinosaurs, those found in the oceans were not technically dinosaurs either. They are called plesiosaurs.
-hunted in a range of ways. Some ate large animals, others are squids and other smaller sea creatures.
We had two experiments this week. The first one was based on the ways that a giant sea reptile may have digested its food. Rocks have been found in the stomachs of fossilized remains, and some scientists think that they might have eaten them on purpose to help break up their food, like a modern day bird.
To demonstrate, we put a scoop of dry cereal into a Rubbermaid bowl and added a few stones. Then the lid was put on, and the bowl passed around to all the kids. They shook the bowl as hard as they could and then passed it on to the next child. When it got back to our host mom, she lifted the lid and we looked inside the cereal had been mashed up at all. It really had! There were a few left in tact, but generally, there wasn't much left but crumbs and powder.
(Other scientists think that the rocks were inadvertently eaten as they scooped up food from the ocean floor. We'll never really know)
Experiment number two:
Experiment number two:
Salt water and buoyancy. We learned that the ocean water is different than our regular water. It has high amounts of salt dissolved in it, and therefore behaves differently. One thing it effects is an object's ability to float.
Our host mom prepared two containers of water. One tap, and one with salt added. Then we dropped an egg into each and watched how one egg sank to the bottom, and the other floated along the top. The kids all guessed which container had the salt and then we learned that the salt helps things float and not sink to the bottom. So the container with the salt was the one with the floating egg.
Scientists believe that the sea reptiles could get so large because the buoyancy effect of the ocean helped them swim around and not sink. Otherwise, they think the animals would have been so heavy, they would have just sunk to the bottom and died there.
The moms drew a simple outline of a pleisaur and the kids added dots inside of it with a washable marker. Then they painted over their dots with water and watched the colours run together to create a more mottled look. They turned out quite pretty, really.
Craft Time: Since some of the animals ate squids, we made a squid craft.
First, the kids were given a large sheet of paper and a variety of bingo dabbers and they went to town with them. They really loved this part. Then when the paint had dried, we rolled them into a cylinder and stapled them closed. To make the tentacles, we used large, fuzzy pipe cleaners that we attached through holes we punched along the bottom. Lastly, we glued on some googly eyes and added a handle on the top.
We ate goldfish crackers, but before they could gobble up their food, they had to 'catch the fish' just like the sea reptiles needed to. Our kids each got a straw, and then by sucking in air, they had to pick up a gold fish and transfer it into their bowls. Once all their fish were caught, it was chow time!
To add a carnivorous element, she also served little cocktail wieners and ketchup. These were a huge hit, and the kids kept asking for more 'baby hot dogs.'
Craft Time part two:
After the snack, we pulled out s time to make our own ancient ocean in a bottle. The kids added blue food colouring to a bottle of water, then added some sand, rocks, sea shells, plastic little plants, and a couple of small figures of aquatic dinosaurs.
Our host made several different sea reptiles and the kids took turns organizing them into different groups. The did it by size, colour, and shape.
Story Time: We read "Oh my! Oh my! Oh Dinosaurs!" by Sandra Boyton.
Wiggle Time: We were basically out of time for the day, but we gave it a quick whirl. A large circle of sting was put on and one person was 'it' and was inside. They were to represent the sea reptile. Then the other kids were animals walking around the ocean. But if one got too near the circle, or even stepped inside it, the sea reptile would grab them and gobble them up.