Paper Mache Paste
Magic Mud Floating Layers: Density Experiment
About 1/4-1/3 cup each of the following:
karo syrup (aka white corn syrup)
corn oil (or other vegetable oil)
optional: rubbing alcohol
optional: lamp oil
optional: food colouring or powdered tempera paint
- clear glass beaker or other tall transparent container
- various items for floating: washer, machine screw, corn flake, rice cereal, raisin, grape, feather, shell, various nuts, coins, wood shavings (try different types of wood here), leaves, stick of chalk, chalk dust, packaging peanuts, buttons, dried pasta, dried beans, a ball of modelling clay and a piece the same size formed into a wide cup shape, etc.
- optional: notebook and pencil to record your results
- Before you layer your liquids, try weighing the same amount of each and record your results.
Which is the lightest?
Which is the heaviest?
What pattern emerges?
Does this pattern hold for all of the liquids? If not, try and hypothesize as to why not.
- If you wish to colour the layers (this makes it prettier, more interesting to look at, and easier to see the different layers), do so before pouring. The colouring should work on all but the corn oil and honey.
- In the order listed, pour each of the liquids over the back of the spoon and into the container so as not to disturb the layer beneath.
- Once you have layered your liquids, try to predict how far each of your items for floating will fall before floating.
- Now try floating a few different items. Revise your guesses if you wish.
- Record your results.
- Try various other items to float as well.
This is an experiment about density. Density is a measure of how much matter ("stuff") exists in a given space. Denser substances have much more material packed tightly together, and lin ess dense substances the matter is more spread out. Denser items have a greater mass for the same amount of volume (valume is the 3-dimensional space that something take up).
Strictly speaking, the densest of the fluids will be at the bottom of the container, with the least dense at the top and each in its ordered place in between. Likewise, the floating items with a greater density should sink to lower levels than those with less density when floated in the liquids. However, you may have experienced something different here. If so, can you figure out what might have happened and why?
Indian Corn Necklace Corn Husk Dolls (external link)
This activity is recommended for kids who will not be tempted to suck on the straws and drink the ink.
plain popcorn (free of oil and salt)
construction paper or similar for background
smaller piece of contrasting colour of construction paper (for vase)
Cut out your vase shape and place it on the background so you can see where you will want your blossom branches.
- Remove the vase and dip one end of the straw into the India ink and place your finger on the top of the straw to seal it. Keeping your finger in place, move the straw to where you want the bottom of your first branch to be. Release the ink by removing your finger.
- While blowing through the straw, direct the ink towards the top of the page to form your branch. This can be tricky, and you may need to add a little more ink if you run out. Be sure to follow the "forks" in the branches as well.
- Repeat for as many more branches as desired.
Once the ink is dry, glue the vase in place, then glue the popcorn blossoms to the branches.
Indian Corn Necklaces
Indian corn, or unpopped coloured popcorn kernels
sewing needle and thread long enough to make a long necklace, with an extra 4" (10 cm) for tying
Remove the kernels from the cob if necessary. Soak the kernels in water for about an hour before starting to make them softer for threading.
- Use your needle and thread to sew the kernels together into a necklace. If you have younger kids taking part, have an adult use the needle, while the child chooses the colour pattern.
- If older kids have trouble, try starting the holes for them.
- Continue threading the kernels onto the necklace as desired.
- Let the corn dry completely before wearing the necklace (otherwise, the colours may transfer).
High Fructose Corn Syrup
In recent years, biotechnology has grown, and we now have ways of genetically modifying crops. Some reasons to do this include inceased production, increased growing season, increased pest resistance, and to provide resistance to herbicides. In fact, the majority of corn grown in North America is now grown from genetically modified seed. Proponents claim that genetic modification may be the easiest way to try and alleviate hunger in countries prone to poor soil and drought. They argue that it would be unethical to deny the use of their seed to populations in these conditions. This is not a point to be ignored: while it is true that we produce far more than we can use, effots to simply send our excess to poorer countries have proved to cause difficulty for local farmers and economies. Aid alone is not a lasting solution.
Opponents to GM (genetic modification) worry that we do not know much about the long term effects of such actions, both on human health, and especially on the effects on the environment. Could the resistance to herbicides spread to create "super weeds"? What effect does this have on soil, insects and especially pollinators? And, since several European countries have banned GM crops, how will this affect trade, particularly for poorer countries to which many of the GM varieties are currently sold? Are we in fact carrying on an experiment that could have catastrophic results?
Further concerns have arisen when the larger corporations involved in GM decided to apply for patents on their inventions. The "terminator" variety of seed is designed to grow a plant which cannot produce its own seeds. This keeps farmers from saving their seed, forcing them to buy new seed each season. Such practices also create fears of seed monopoly, and food supply control, as well as concerns arising should those changes cross varieties or even species over time. It also crosses into the realm of religion and ethics: should we be tampering with the code of life? Do we understand the technology and its implications well enough to do this in a predictable, responsible way?
High Fructose Corn Syrup
High fructose corn syrup is one of the most widely used sweeteners in North America, particularly in the United States. It is made by separating the starch from the kernel and using three or more different enzymes to break the starch down into glucose and then further so that about 60% of it is converted into fructose. The result is a substance that is sweet and acts as a preservative. This has chemical similarities to cane sugar, but is slightly different. Since corn is grown throughout North America, corn syrup of all types is a cheap and readily available sweetener. It is found in most processed food including soft drinks, breads, crackers, low-fat foods (used as a filler and preservative), luncheon and other processed meats, cookies, breakfast cereals, jams, frozen desserts, frozen meals, condiments and fast food.
The controversy comes from the belief that there is a connection between the increasing obesity of the population and increases in diabetes and the use of corn syrup (especailly the high fructose corn syrup). It is unclear where the causation lies: are people getting fatter and diabetic because of the sweetener, or because of poor dietary choices in general regardless of the sweetener chosen? How much of a difference do natural vs. processed sweeteners make on general health?
It would seem that this is a combination of availablility and the way we react to artificial/processed sweeteners. Since it is cheap (made cheaper through government farm subsidies), its use has dramatically increased. Sweetened foods have become sweeter, and foods that weren't sweetened at all a few decades ago are now, as a way of improving food preservation.
Several studies have also shown that people who consume processed or artificial sweeteners have an increased desire to continue eating. One of the sources of this information can be found here. Another article on the subject with references can be found here.
Other studies have shown that people react in the same way to high fructose corn syrup as to "regular" (refined cane) sugar. Even if there is no appreciable difference in terms of health and nutrition between the two, the substantial increase of use of high fructose corn syrup (and its close relative, modified corn starch) is unhealthy because it is present in huge quantities in foods throughout the supermarket, and in places and quantities most people would not expect.