The following are excerpts from our Science Blog.

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2 The following are excerpts from our Science Blog. Tub Tints & Polymer Crystals into each cup. We discussed what the kids were observing, made lots of guesses, and asked lots of questions as the fizzing tablets dissolved and the water became red yellow, and blue. We talked about the 3 states of matter and observed that we added a solid to a liquid and created a gas! Then we added about a teaspoon of Jelly Crystals - super absorbent polymer crystals. We discussed how all matter is made up of things that are too small to see with our eyes (atoms and molecules) and that polymers are long chains of molecules. We waited an hour for the crystals to fully absorb the water, then we observed and described what happened to the super- absorbent polymer crystals now fully hydrated. We measured and described the relative size of both a dehydrated crystal and an expanded and hydrated globs and compared the two. Then the kids put a layer of red crystals in the bottom of a Baby Soda Bottle, followed by a layer of yellow, then blue and finally a red layer. At first there are only red- yellow- blue- red layers, but as the colors mix (overnight) the area where the red touches the yellow becomes orange, the area where yellow touches blue becomes green, and the area where blue touches red becomes purple. The next morning the kids can observe their rainbow tubes that now have distinct red, orange, yellow, green, blue, purple layers. Sorry indigo and violet! Is black really black? We filled small plastic cups halfway with water. Near the center of a round piece of filter paper, the kids made small dots of black using black Vis- à- vis (water soluble) markers. They cut green pipe cleaners in half and dipped each piece in water and shook off the excess. This helps jump- start the wicking action. Then we stuck each pipe cleaner through the center of each piece of round filter paper and placed the filter paper over the rim of the cup so that one end of the pipe cleaner was touching the water. Then we put this experiment aside and worked on the next experiment. Eventually the water was sucked up the wick and drawn into the filter paper. As the water crossed over the black ink it dissolved the ink, and carried it from the center toward the edge of the filter paper. The bursts of colors we observed on the filter paper proved that black is really a combination of colors. The science of chromatography! School Spear It - Get back into the school spirit and learn about polymer chemistry. You ll need a Zip- Lock bag, water, paper towels, and some pencils with ROUND edges. If you don t use the ones with round edges, expect to make a big mess! You might want to practice this over a sink first. Fill the bag half full with water and then seal the bag. Ask your kids, What would happen if I tried to push one of these pencils through the bag of water? Here s the cool part! Hold the pencil in one hand and the top of the bag in the other hand and push the pencil right through one side of the bag and half way out the other side without spilling a drop. Continue to boost your school spear- it by jabbing the remaining pencils through the bag. Hint: the pencils must be very sharp! What is the science behind this cool trick? The plastic bag is made out of long chains of molecules called polymers. This gives the bag its stretchy properties. The sharpened pencil slips between the molecule strands without tearing the entire bag. Believe it or not, the long chains of molecules seal back around the pencil to prevent leaks. Diaper Chemistry This activity will introduce your kids to the chemistry of super absorbent polymers! Sound fancy? Have no fear you'll be using the material found inside of a baby s diaper! You ll need a diaper, a one gallon Zip- Lock bag, small plastic cups, Copyright: 2015 by Mike Ashcraft/ All Rights Reserved/ 6501 Lomas Blvd NE/ Albuquerque, NM 87110/ / page 2

3 food coloring, and scissors. Use a pair of scissors to cut off the paper or plastic outer layer around the entire diaper. Separate the cotton, paper, and plastic layers of the diaper. Place the layers of diaper into the plastic bag. Seal the bag and shake it for about one minute. You should see white powder granules collecting in the bottom of the bag. Now, without opening the bag, scoot the cotton, plastic, or other large pieces of material toward the top of the bag. Keep the material at the top of the bag as you shake the bag again. This will allow the powder to settle down to the bottom without getting picked up by the cotton again. After you have about a teaspoon of powder in the corner of the bag, slowly open the bag and discard the large pieces of material. Now, carefully pour the powder into a small cup. Have your child add 1 tablespoon of water at a time to the powder and watch what happens. You can also add food coloring if desired. As the powder absorbs water, it becomes bigger and bigger and turns into a gel. A teaspoon of this material can often absorb over 100 drops of water. That's how the baby s bottom stays dry! This amazing powder, scientifically called sodium polyacrylate, is considered to be a super- absorbent polymer because it can absorb hundreds of times its weight in water! Sodium polyacrylate is a super absorbent polymer that consists of chains of identical units, known as monomers. Sharpie Science Shirts We made small designs about the size of a quarter on white t- shirts. Then we dropped rubbing alcohol on the designs very slowly. The alcohol spreads across the fibers of the t- shirt and acts as a SOLVENT on the Sharpie ink producing nice bursts of color. We talked about the meaning of words like dissolve, and SOLution, SOLid, SOLubility, and SOLvent. It is a science of SOL tie dyed t- shirt. Screaming Balloons- This activity is kind of like that motorcycle rider in the metal sphere at the circus. We took a clear plastic balloon, put a hex nut inside, inflated the balloon, tied it off, and began what Steve calls the MOST ANNOYING SCIENCE EXPERIMENT EVER. We just held the balloons in our hands and began a spinning- swirling motion. Thanks to the inertia supplied by our hands and the centripetal force of the balloon, the nut flips up on its edge and spins around the inside the balloon vibrating to making a fun (annoying) sound. Centripetal force is the inward- seeking force that causes the nut to go in a circular motion. The gravity of the sun is the centripetal force that keeps our planet going in a circular motion. Good thing if it weren t for that force, we d go flinging off into space. Ballooning Baby Bottle This is a classic dating back to the original Mr. Wizard from the 1950 s. You ll need a plastic baby bottle, a blind baby bottle nipple (nipple without a hole in the tip), safety glasses, seltzer tablets, and water. Put on the safety glasses. Put 8 ounces of water in the baby bottle, drop in two seltzer tablets, and quickly cap the baby bottle. Your kids may expect water to come shooting out of the nipple since they don t know it has NO hole. As carbon dioxide gas is being produced, the nipple will expand filling with gas. When the bubbling stops, invert the bottle, and allow the water to flow into the nipple and the gas to rise into the bottle. Look at the graduations on the bottle to see the gas that was produced. Talk about why this cannot be an accurate way of measuring the true volume of the gas produced and see if kids can catch the potential error of non- standardized blind- nipple stretchiness. Say that ten times fast! Don t go to a department store looking for blind nipples. You won t find them. We found ours here of course. baby- bottle Seltzer Rockets We got a film- developing booth to save us some film canisters (Fuji - clear ones where the lid fits inside), and we bought lots of seltzer tablets. First, we filled our film canisters with water. We talked about the liquid properties of water. We showed the children the seltzer tablet and talked about the properties of this solid. Then we plopped the tablet into the water and let the children see the bubbles. We asked them to predict how long the chemical reaction would last? We timed the reaction. We let them hold their hands over the cup and feel the bubbles. We talked about the properties of gases. We threw the liquid in the film canisters into the waste bucket. Then we demonstrated a launch. We refilled a canister about 1/3 full of water. We broke off a ¼ piece of the seltzer tablet and dropped it into the water, quickly placed the lid on, and dropped it lid down into an empty paper towel Copyright: 2015 by Mike Ashcraft/ All Rights Reserved/ 6501 Lomas Blvd NE/ Albuquerque, NM 87110/ / page 3

4 tube, being careful to aim it away from the kids. In a few seconds the canister flew out at warp speed! When we combine bicarbonate of soda (solid) with water (liquid), it created bubbles of carbon dioxide (gas). So much gas was produced that the film canister couldn t hold it all and the gas pushed the lid off the canister with such force that it was propelled out of the tube POW! Can you guess what the kids began shouting? Do it again! Do it again! But repeating the same thing wouldn t be science now would it. So, we donned our attractive and protective eyewear and headed outside for some real science. We brainstormed what variables we could change that might have an impact on the reaction time. Then we changed ONE variable at a time, tested it, and recorded how long it took for the explosion to happen. We changed the volume of water, the temperature of the water, the amount of seltzer tablet to use. You could make it a race how many times can they do it in two minutes. Sneak in some math measure how high or far the lid flies. What would happen if you capped the canister with a balloon? Cheap Wal-Mart Beads Madison said, I had an idea of doing an art project with you. I thought you could make bracelets. I went to the store to buy you some beads with money from my allowance. The colorful beads were too expensive, I could not afford them, so I could only get these white ones. We made bracelets, and then we took the kids outside. As soon as we got out in the sun they noticed the beds stared to change colors. Wow! They were shocked to realize they had been tricked. We explained to them that the cheap white beads were actually ultraviolet (U.V.) light detection beads that change color when exposed to U.V. rays. These beads are very good at detecting and indicating changes in levels of UV radiation. Madison told the group that brown prescription bottles were colored that way to protect our medicine from damaging UV rays. When we put UV beads in the prescription bottle we could see NO color change. Looks like the little brown bottles do a good job! After we discovered this, we decided to conduct some experiments. We discussed some of the things people use to block UV rays, like sunglasses and sunscreen. We decided to compare how two different types of sunglasses blocked the UV rays. We predicted that the $5 sunglasses labeled as 100% UV protection would block the sun better than the free kids meal toy sunglasses. We found that the beads protected by BOTH sunglasses were colorless when we removed the glasses. We concluded that more research would be needed to conclude anything! Sunscreen Experiment - When it comes to sunscreen, there are lots of SPFs (Sun Protection Factors). We thought, What if we protected the UV beads with different SPF sunscreens. Since these beads are very sensitive to changes in UV, we decided to conduct an experiment - using the beads to look for differences in how bright the color of the beads would be when exposed to direct sunlight. To find out which sunscreens work best, we collected four strengths of sunscreen (SPF 2, 30, 50 & 70). First we coated some zip top bags with the difference strengths of sunscreen similar to the way we would apply it to skin. We labeled each bag with the SPF of the sunscreen we applied. Then we placed the bracelets we made into the zip top bags. We put NO sunscreen on one bag for a control. Then we exposed the bags to direct sunlight and observed and recorded the results. We observed a big difference between the SPF 2 and the SPF 70, but NOT a big difference between SPF 30 & SPF 50. We also observed that ALL sunscreens let some UV radiation through. Copyright: 2015 by Mike Ashcraft/ All Rights Reserved/ 6501 Lomas Blvd NE/ Albuquerque, NM 87110/ / page 4

5 Windbags Product - We purchased some "Windbags" - long plastic bags in the shape of a tube. We tied a knot in one end of the bag, used my hand to make the open end into a small hole, and asked a volunteer to blow four large breaths into the bag. We compressed the air he blew in down to the knot to see the volume of air blown in and how many more breaths it would take to blow up the whole bag. The kids predicted that it would take about 40 breaths to inflate the whole bag. Then I challenged them to race me. The volunteer tried to continue to inflate the bag by blowing into the small opening, but I held the open end of the bag approximately 10 inches away from my mouth, and blew one BIG breath - as hard as I could you into the bag. The entire bag inflated and the race was over in a flash. And the crowd went wild! What s the science of this? Remember Bernoulli s Principle. When you blow a stream of fast moving air into the bag, you create low pressure. So, the higher pressure air in the atmosphere shoves its way right into the bag along with the air from your lungs. This is the same way they inflated the hot- air balloon in Hot Air Henry the book we read earlier. They put a pretty large fan outside of a much larger opening and use the fan to help push some atmosphere into the balloon. Waterproof Paper Challenge: We gave the kids the challenge of dunking a wad of paper towel COMPLETELY under water for 10 seconds and keeping the paper towel COMPLETELY dry using only a small cup and a piece of tape. The kids eventually discovered that if they taped the wad of paper towel to the bottom of the cup and submerged it upside down into the water, the bubble of air trapped inside the cup separates the paper towel from the water and keeps the wad from getting wet having no way to escape the air kept the water from entering. Now - tilt the glass while under water what happens? Huff Puff - Place an empty 1- liter soda bottle on its side. Wad up a piece of paper into a loose pea- sized ball and place it in the neck of the bottle just inside the opening. The challenge it to try and blow the paper ball into the bottle. This falls into the it s harder than it looks category. Huff and puff all you want, but the ball will keep coming OUT of the bottle. How does this work? Remember that the bottle is not empty, but is COMPLETELY full of air. As you blow air into the bottle, you force the air that was already in there to blow out the only place it can escape. This escaping air blows the paper ball OUT! Try blowing hard or soft. Try blowing close to the bottle or further away. What do you think would happen if instead of a loose, pea- sized ball you made a more compact spit wad? What if the opening was bigger? What if you created another escape hole? Huff n Puff Challenge: We gave the kids an empty 1L soda bottle and a small wad of paper towel. They placed the small wad of paper towel into the neck of the bottle. Their challenge was simply to blow the wad of paper INTO the bottle. Remember the bottle is not empty, but is COMPLETELY filled with AIR (takes up space and exerts force)! This definitely falls into the harder than it looks category! As you blow air into the bottle, you force the air that was already in there to blow out the only place it can escape. This escaping air blows the paper ball OUT! Try blowing hard or soft. Try blowing close to the bottle or further away. What do you think would happen if instead of a loose, pea- sized ball you made a more compact spit wad? What if the opening was bigger? What if you created another escape hole? Copyright: 2015 by Mike Ashcraft/ All Rights Reserved/ 6501 Lomas Blvd NE/ Albuquerque, NM 87110/ / page 5