A collection of moments from our Grade 7 learning community
Have you ever performed a dissection? We learned that dissections were (and are) a tool that scientists use to learn more about the biology and anatomy of plants, animals, and even people. We performed a ‘mock’ dissection using Twinkies! Our students needed to practice their precision, observation, and patience when taking samples, making incisions, and removing ‘organs’ (filling) from their ‘test subjects’.
As part of our ‘Spooky Science’, our class investigated a mysterious substance. Not quite liquid, not quite solid, but a little of both… this is a non-Newtonian fluid! You can make this substance at home by mixing a 2:1 ratio of cornstarch to water. Once mixed well, this substance can behave like a solid and like a liquid!
We tested this substance in a variety of ways, including: slapping/poking the surface, sinking a spoon into it, rolling it into a ball, and trying to pour it into another container. We learned that when we kept the substance still (ex: holding it in our hands without moving), it often would pour or drip like a liquid. But if the substance was being moved (ex: rolling it between our hands), it would take on a more solid appearance.
Check out the video below to see how this substance behaves when placed on top of a speaker cone:
Some questions to discuss at home:
Have you ever eaten a truffle? Black and white truffles are some of the most expensive and rare types of edible fungi! They are sometimes foraged in the wild, or they may be cultivated (grown) in special truffle orchards.
Truffles have a reciprocal relationship with the trees in the forests. They grow under the ground, near the roots, and have are symbiotic (the trees and the truffles help each other survive). We learned more about amazing, weird, and wonderful fungi during our mushroom dissection this week!
Today for SCI-FRI, our class and Ms. Ramen’s class investigated some unusual fruit and vegetables! Many of these fruits and vegetables are commonly used in different cultures and found in different countries across the world. We used our observational skills to draw a diagram and describe each of the fruit and vegetables. Do you recognize any of these fruits/vegetables?
Above, left to right: pink pineapple, mo qua, rambutans
Below, left to right: pomegranate, young coconut, apple pear
After we made our observations, we cut open the fruit and vegetables to examine the inside. We noticed there were many different colours and shapes of seeds. Many of us have tried these fruits and vegetables before!
Above, left to right: lotus root, custard apple, papaya
Below, left to right: dragon fruit, bitter melon, mangosteen
Some questions to consider:
-Why are some of these fruits and vegetables commonly eaten in some countries and not others?
-How could we learn more about all the interesting, tasty, and unusual fruits and vegetables in the world?
Today, we investigated how vinegar and baking soda would react when mixed inside a pumpkin! Check out our results below:
Our class is exploring ‘Spooky Science’ this month! We began by exploring these ‘PH potions’… by using cabbage juice as an indicator, we were able to look for colour changes for acids (pink) and bases (blue)!
What makes for an accurate and informative Science experiment? Well, we need to make sure we have a strong hypothesis, a clear control, and a variety of variables. Today, we began our investigation into the question: how can we create the largest, most dramatic eruption when mixing Mentos and soda?
So far, we have tested 2 liter bottles of Diet Coke, Coke Zero, Diet Pepsi, Pepsi Zero, Pepsi, Orange Crush, generic brand cola, and soda water (our control). We noticed that the Diet sodas performed very well.
Now, as a Scientist you must decide… what variables should be manipulate to get different results? Should we test smaller bottles of pop? Different kinds of soda (ex: Sprite, Root Beer)? Should we use different amounts of Mentos? Would other candies have similar effects?
We will continue this investigation over the next week!
Taking fossil evidence and turning it into a ‘reconstruction’ (an estimate of what a living dinosaur might look like) is challenging work! Often, fossils are not fully complete and are missing lots of key pieces. Usually organs, skin, and feathers do not fossilize as easily as bones and teeth. Special artists try their best to use the ‘clues’ left by fossils to imagine what living, breathing dinosaur species would look like!
These ideas change over time, with more information and more fossils. Check out what Scientists used to think dinosaurs looked like below!
Above: an early sculpture of life-sized iguanodons in Crystal Palace Park.
Below: a more recent artist’s reconstruction of an iguanodon.
Who knows what we will learn about dinosaurs in the next 10, 50, or even 100 years!
Today, our botanists continued to examine the structure of flowers and plants! We dissected a daffodil, a tulip, and an iris. We noticed that each of these flowers had pollen inside! We also examine the pollen and stamens under our microscope (pictured below):
Image: the stamen (left) and pollen (right) of a daffodil under a microscope
Our class created our own version of the famous ‘elephant toothpaste’ experiment! To do this experiment at home (with adult permission and supervision), you can…
-fill an empty plastic bottle or cup around 1/2 way with 3% hydrogen peroxide (if using a higher %, please wear gloves and eye protection)
-add a large squirt of dish soap
-optionally, add food colouring and/or peppermint extract
-then, in a separate cup mix a large spoonful of instant yeast with some warm water for 30 seconds (until dissolved)
-quickly and carefully pour the yeast mixture into the hydrogen peroxide mixture and step back
We learned this experiment creates and exothermic reaction, which means it gets hot! We noticed that when we increase the amount of soap and yeast, the bubbles continued to form for a much longer amount of time.
Pleases note: Always be careful when doing Science at home, and make sure to have adult supervision and permission.