Category: Fun Science Activity (Page 93 of 112)

Weekend Science Fun: Rock Around the World

Does your budding geologist pick up rocks everywhere you go? Have a buckets and bins of rocks at home?

I just came across a terrific program where children can learn more about rocks and minerals and help scientists with their research. Your child can choose a rock and send it to scientists at Arizona State University for analysis.

According to the Rock Around the World website (http://ratw.asu.edu/), you may send a rock 2 to 6 inches in size, although the preferred size is about 4 inches long. It should also be clean and free of dirt. The “About the Program” link (http://ratw.asu.edu/program.html) will give you more details and the address to send the rock.

Be sure to spend time to see the rocks that have already been sent in from your area and from around the world, and check out the rock of the month.

Tomorrow we will meet the scientist who started this program in “Meet the Scientist Monday.”

red rocks

Weekend Science Fun: Recycling Paper

Our recycling paper activity this week requires more materials and time than most of our previous projects, but is fun and can become an enjoyable hobby. It can also be messy.

Gather:

  • Either a blender or hand blender – probably should be dedicated to making paper, because the paper dulls the blades.
  • Water source and measuring cup
  • Paper to recycle
  • Optional 1:  dried flowers, glitter, cotton dryer lint, etc.
  • Optional 2:  seeds to make seed cards
  • Waterproof bin to hold the wet paper pulp, large enough to accommodate your largest deckle/mold
  • Sponges
  • Towels or felt to spread out wet paper for drying
  • A deckle/mold*
  • Tray to hold paper while sponging (optional, but helpful)

*A mold is basically a window screen stretched tightly over a wooden picture frame and stapled, and the deckle is another frame of the same size overlaying it to form the pulp into shape. You can buy them or make your own. I would recommend you have multiple deckles/molds on hand if you are working with several (impatient) young children.

Set up in an area where a wet mess will be easy to clean up. Probably outdoors would be best at first.

The following instructions have worked for us. If you do some research, I’m sure you’ll find a number of other methods. Be sure to play around and see what gives the best results for you.

First, tear up the paper to be recycled into pieces roughly two inches in diameter or smaller. You only need a few sheets at first. Try papers with different textures, such as construction paper scraps, old newspapers, used computer paper, etc. Colored paper is fun. We found construction paper gave us a fine, smooth paper that was flexible. If we used a lot of newspaper, the resulting paper tended to be thicker and lumpier. Find the mix you like best.

papermaking

Add paper scraps from one piece of paper into the blender with four cups of water. Blend until the paper is no longer recognizable and looks “pulpy.” Pour into the waterproof bin. Repeat five times. After that, use less water, either two or three cups depending on the type of paper and how strong your blender is. Only make as much as you think you will use.

papermaking

If you are using a hand blender, you might want to soak the paper with water in the bin overnight before pulping. This loosens the fibers. You could even compare soaked overnight versus not soaked and see how the resulting paper looks and feels.

papermaking

Once you have enough pulp, add your optional 1 materials and stir them in. You may add them over time or compare different additions in different batches. Swirl your pulp so the fibers are suspended evenly.

Place the mold/screen on a surface and line up the deckle on top of it. Firmly grasp the two pieces together at the sides. Make sure your thumbs stay on the deckle frame and don’t slip into the screen, or you will have paper with thumb-shaped grooves in the sides.

Now show the children how to dip the mold/screen and deckle sandwich into the pulp (deckle side up), swirl it and then gently lift straight out. Capture an even layer of pulp, while the water passes though. This step is definitely an art. Play around with it. If you are disappointed with an uneven pass, you can dump the pulp back in and start again. Paper is forgiving that way.

papermaking

The wooden frame is the deckle. You can use other shapes, like embroidery hoops or large cookie cutters, to hold the pulp into shape as well.

papermaking

Here is a screen mold that has a plastic support, after the deckle is removed. We use a tray to catch the spilling pulp and water.

If you’d like to make seed cards, now is the time to sprinkle some seeds (optional 2) into the surface of the pulp. Spread them about as far apart as the package recommends. If they are too close, you can always tear the card apart for planting.

papermaking

Once the pulp is ready, it is time to press out the excess moisture. Our commercial paper making set came with a second screen. Set the second screen on top of the pulp, if you have one. Then press the pulp with sponges to remove excess water. Wring the sponge and press again. Hint:  the more water you remove at this step, the less time it takes to dry. Encouraging the children to spend time at this step also allows others to be scooping out their pulp at the same time.

Now set the paper onto your felt or towels and gently peel away the screen. Note:  if you use towels, check for textures in the fabric. Any textures in the towel will often transfer into the paper. If you choose felt, which is smooth, make sure it is colorfast beforehand.

I like to lay our towels/felt on the top of our clothes dryer. It is a flat surface I don’t use, and the heat from when the dryer is running speeds up drying time.

Warning:  never dispose of paper pulp down the drain. If you have pulp left, let the kids press it into small molds or shape it free form and let it dry. The thicker the form, the longer it will take to dry.

Although thought of as an art, there are schools that teach paper-making science. Think of ways to change how you make the paper and then test for differences in your final product. What kind of characteristics could you measure? I have seen recipes for paper that call for an addition of cornstarch, and read elsewhere that cornstarch makes the paper more likely to mold and/or give off bad odors. How would you test this? If you think up and perform an experiment with recycled paper, be sure to let us know.

For more information:

Making Your Own Paper by Marianne Saddington

The Papermaker’s Companion: The Ultimate Guide to Making And Using Handmade Paper by Helen Hiebert

Weekend Science Fun: Loads of Lemons

This week the lemons are literally falling off the tree, so it is time for a round up of science experiments with lemons.

lemons

Lemon soda/pop
One of our favorite crazy chemistry projects is to try to reconstruct soda/pop flavors using ingredients found around the house and some fizzy water.

Gather:

  • Measuring spoons of various sizes
  • Hand juicer
  • Lemons
  • Limes
  • Oranges
  • Spices such as cinnamon, cloves, ginger, nutmeg
  • Unflavored carbonated water
  • Sweetener of choice
  • Small drinking cups or glasses
  • Slop bowl for dumping rejected recipes

If you supply a lemon soda to imitate, tape a piece of paper over the ingredients until the children have tried some recipes. Certain of the ingredients in citrus-flavored sodas were unexpected to us.

Or just allow them to create something that tastes good.

Have the children measure a standard amount of carbonated water into a glass and then add flavors. We’ve done this many times with many different friends and we’ve found that everyone enjoys it once they realize they are truly being given free rein to experiment.

Lemon batteries – a classic

Lighting up an LED with a few electrodes, wires and lemons is really exciting and it does work, although it is not easy.

Gather:
Lemons
Zinc electrodes (zinc coated nail works in a pinch)
Copper electrodes (or penny or copper wire)
Connection wires – with alligator clips is a plus
LED (available at hobby shops)

Hints:
1.    Use more than one lemon. Three or four hooked together works best, with two electrodes per fruit.
2.    Make sure you alternate electrodes, zinc/copper/zinc/copper. The zinc is negative, copper is positive.
3.    The LED also has a positive and negative orientation, so make sure it is in the circuit in the correct orientation. The slightly flattened side is the negative side.
4.    A trick I learned the hard way is to place the electrodes pretty close together. The figures often show the electrodes at opposite ends of the fruit, but moving them closer to each other works better.

This CSIRO site shows how to set up the lemon battery with the electrodes close together.

Lemon Juice as an Acid
Ever make a fizzy volcano or a film canister rocket with vinegar and baking soda? You can substitute lemon juice for the vinegar and still get similar results. If you add a squeeze of dish detergent with the lemon juice before adding the baking soda, it will froth even more.

Germinating Lemon Seeds
Save the seeds of the lemon when you make lemon juice. Wrap them in moist paper towel as described in the germination test post and keep them moist. In time, the seeds should sprout and you can grow small lemon trees. Lemons are susceptible to freezing, so only set them outside when temperatures are above freezing.

For the botanists:  Interestingly, many citrus can produce seeds without the flower being pollinated. Those seeds are identical to the parent, rather than being a mixture of traits.

lemons

We have talked about science with lemons before in previous posts:

When studying acids and bases, use lemon juice as a test substance. If you want to make a soft cheese, lemon juice can be used to curdle milk.

When you are finished, celebrate your science by making some lemonade, lemon cookies, lemon pie or lemon bread. Yum!

Let us know how your experiments turn out or if you have any great ideas for using lemons in science experiments.

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