The end of summer is always a busy time. That's the only excuse I can give for not finishing up my last Science and Swim post. The last event focused on one of my favorite watery things -- bubbles!
First up, we made bubble prints. It's really easy. Just water down washable paint with water -- anywhere from 25 to 50% paint, depending on what you're using. Then add a few tablespoons of dish soap. Mix well and place in a dish or pie plate. Use a drinking straw to blow bubbles in the liquid, then quickly place a piece of paper over top, popping the bubbles against the paper. Lift and enjoy your bubble print!
Another fun thing to do is to make a bubble blower for bubble snakes. Just cut the end off a water bottle and use a rubber band to attach some scrap cloth over the end. Dip the cloth in bubble mix and blow through the neck of the bottle. Voila! Bubble snake!
For the big finish we just had to do the classic giant bubble. Grab a kiddie pool and a hula hoop. In the pool make a mixture of 10 cups of regular Dawn dish detergent (not the antimicrobial kind) and 5 gallons of distilled water. Mix is well, but try not make bubbles or foam. Place the hoop in the pool and have a kid stand in it. With a person on either side, quickly life the hoop, creating a giant bubble around the person in the pool! Awesome!
This week's Science and Swim was a really fun project that explores buoyancy. We made submarines using recycled water bottles. When placed in water, the bottle fills with water, pulling it down below the surface, then, by blowing air though an attached straw, the water is forced out and the submarine rises again.
One of the things I love about this project is that is clearly demonstrates that both water and air take up space -- they have volume and can be displaced. Too often kids think of air as "nothing," or as "empty." This shows that to be untrue.
Also, it displays the importance of density: the bottle can be filled with water or air, but only with the denser water does it sink. You're filling the same exact space, but one is much heavier (i.e. it has more mass), and it is therefore a denser material.
All that said, let's get to the build! You'll need the following materials: a disposable water bottle, a drinking straw with a flexible neck, waterproof tape (I like duct tape), pennies or washers, rubber bands and scissors.
Start by using the scissors to place three small holes in the bottle along one side -- by the neck, in the middle and near the base. These will let the water in the submarine.
Next attach the straw. Place the end with the flexible bit into the neck of the bottle and secure with tape. Be sure that the straw is attached to the topside of the bottle, opposite the holes. Also be sure that the piece inside the bottle is aimed up, to allow the maximum amount of air to escape as the bottle fills with water. Bend the long part of the straw up, so that is can be used to add air. Use tape to completely seal the opening of the bottle.
To create ballast, make a stack of pennies and wrap them in duct tape. I'd suggest starting with three stacks of six pennies and adjusting as needed. Use rubber bands to secure the pennies to the underside of the submarine.
This is a great area of experimentation and exploration. How many pennies are need to get your submarine to fully submerge? Is it even possible to get the submarine to fully submerge? Does it matter where you attach the pennies along the body? Do you need to place an equal number of pennies in each stack? What happens if you don't?
To test the craft, place it in water, the underside down and let it slowly fill with water. Once it no longer sinks, blow air through the straw and it will rise again. You can even let it sink the bottom of the pool, dive in and "rescue" it from the depths.
Once you're happy with the number and placement of the pennies, dry off the submarine and tape the stacks of pennies on. It'll be easier to play with. Have fun!
Our most recent Science and Swim at Belvidere Pool was the most well attended yet! Perhaps the article in the Warren Reporter helped. This week we made sailboats with easy-to-find materials and lots of awesome duct tape then set them afloat in the pool. I swear the toddler pool looked like it had spawned an armada!
To set the mood, let's start with your morning earworm: "Come Sail Away" by Styx.
Now that we're all humming along together, we can get building! First you need to assemble materials: A tray to act as the hull (we used small cardboard ones donated by Nature's Harvest), a bamboo skewer to act as the mast (a small dowel or pencil will also work), lots of colorful duct tape, a small amount of modeling clay, scissors, wax paper for the sail and an old foam egg carton for the rudder.
You start by covering your hull with duct tap, top, bottom and sides. If you want, you can also build up the sides a bit with tape, to prevent water from coming onboard.
Now you need to attach the mast. Make a small ball with the clay and place to towards the bow of the boat. Then stick the skewer into the clay. Mold the clay around the skewer to hold it in place. Cover this well with duct tape. If you have the time and ability, punching a hole in the hull and pushing the mast through a bit, then adding a bit of glue and covering with duct tape will add more stability to your design.
Next we need to attach the sail. I chose wax paper because it's relatively waterproof and inexpensive. That means you can try lots of different sail shapes, if you like. You don't have to stick with the standard rectangle. Try a circle or triangle or a octagon, if you like! Attaching the sail is very simple: just cut two slits in the paper with scissors and slide it onto the mast. If you plan to change shapes often, using a bit of tape to build up spots on the mast to hold the sail in place will suffice. For more longevity, use a bit of scotch tape to hold your sail onto the mast. In either case, be sure to create a "cup" in the sail to catch the wind.
Over the course of our build at Science and Swim, we experimented with lots of ways to make our sails sturdier, as it was pretty windy. One mom had a great idea: putting a strip of duct tape on the top and bottom of the wax paper to add stability. We also experimented with creating tie lines with tape and using materials like old plastic bags and ziplocks for sails. You can even build a sail out completely of duct tape. This is where prototyping is important! Keep modifying that design until you get it to do what you want!
It's also fun to add a rudder, so that you can steer your boat. (This also illustrates an important idea about fluid mechanics, by the way.) To make the rudder, just cut a piece of foam from your egg carton, cover it with duct tape and cut out a small wedge. Then make a slit in the back of your boat and fix the rudder in place. By changing the angle of the rudder, you can change the direction of the boat. It's a lot of fun to experiment with different rudder shapes too!
Then it's time to take the boat to the water and give it some wind! If you have rough waters, you will need to replace your sails, as the wax paper will eventually break down and start to fall apart.
One creative young man, used leftover egg carton pieces to make fun characters for his boat. You can too!
Have fun and enjoy sailing the high seas... or your backyard pool!
Heading the pool, but don't have the money to spend on fancy pool toys? Here's one you can make yourself really easily! We're making a dive toy that you can chase to the bottom of the pool. Total cost: under $1 and under 5 minutes of your time
All you need is some duct tape and a rock. Be thoughtful with your choice of tapes and consider the color of the bottom of the pool. You want to pick something that you'll be able to see. (This presumes you have duct tape hanging around that house. If you don't, I weep for you. Now go get some!)
First we need to make a loop using the tape. Rip off a piece about 12 inches long. Fold one side lengthwise to the center and press well.
Fold the other side up to create a non-stick strip. Use a 1-2 inch piece of tape to join the ends together, forming a loop.
Now pick a clean rock (nothing TOO big) and cover it with tape. Be sure to press down any strange folds or lumps and generally try to smooth the tape over the rock.
Now, put the loop on top of the rock and us coordinating tape to attach it. Don't skimp or you'll end up with a loop and no rock when you retrieve your toy from the water.
And there you go! Hours of diving fun! The rock will drop to the bottom and you need to dive in and grab the loop to retrieve it. Just be careful, of course, not to throw this AT anyone.
Here's one that my daughter made actually underwater at the Belvidere Pool.
Another super simple idea is to take an old plastic Easter egg, put a few small rocks into it and decorate it with duct tape. This is also really fun to dive for.
