On November 18, 2005, my fourth grade students hosted a science festival at Denali Elementary School in Fairbanks. We reserved the cafeteria, and it worked well for this event, but we could only host one classroom at a time. All of the kindergarten through second-grade classes attended, about 175 kids, and lasted most of the day.
Preparation for the festival began the week before. Planning actually started even sooner than that, but I began preparing the students when we were about 12 days away from the festival day. I depended heavily on a book by Tik Liem, called Invitations to Science Inquiry. Some of the names for our stations came from this book. Others we made up because we wanted them to sound fun. The book was loaded with demonstration ideas that required common materials that you could find around the house, or pick up at any general store. Things like string, rulers, paper, canned goods, plastic bottles, and pennies were the types of things I used. A couple of the adults who visited asked me where I got all of the equipment, and I told them that I cleaned out my basement. That was true. The basement was a mess the morning I went down to my work table to start putting together some of the stations, and as I was organizing things I kept finding stuff that I saw a use for in the festival.
Each day or so I introduced my students to a new activity. I wanted each them to know a little bit about as many of the activities as possible. Some of the activities lent themselves to group presentations better than others. We had a lot of fun as a class trying things out and figuring out how they worked, and most importantly, how they might not work. My presentations to my own students were also the way that I field tested the activities. If the kids, the fourth-graders, couldn't understand or manage the activity, then I figured that probably younger students would have difficulty also. My plan was to have about 15-20 stations, with the visiting classes in pairs so that there would always be a few "open" stations. When students were done at a station, they would have a choice of those that were open for their next stop. My students escorted the younger students to the open stations. Each half-hour a new class would arrive, and the fourth-graders would rotate to manage a new station. One of the fourth graders came up with the idea of numbering our stations (We made signs, so a number was added to each sign) so that the station hosts would know which station they should manage next. This complicated the program a little bit for me, their teacher, but it made the event more fun for them. Additionally, they had to learn about more than one demonstration, so it was an additional challenge for them to learn about several science concepts. In some cases, their understanding of the concepts was pretty sketchy, but in that case they got to wonder along with their younger peers.
The Demonstration Stations
Most of the demonstrations were engaging to the kids because they relied on what is called a discrepant event. A discrepant event is an unexpected outcome. For science inquiry, this causes a person to begin asking questions and is a useful way of beginning an investigation. In the case of the science festival, the investigations were all fairly spontaneous. That's one of the things that made it fun, though, because it resembled play and stimulated an awareness of common phenomena in the everyday world.
The rest of this article will briefly describe the different stations that my students had at our science festival.
Hole in the Hand
Hole in the Hand demonstrated a visual/perceptual anomaly. If you take a paper towel tube and hold it in front of one eye, keeping both eyes open, and hold your other hand out near the end of the tube, when you stare past your hand a hole appears in your hand.
Tin Can Telephone
Tin can telephones are great demonstrations of how sound and vibration are related. It's an age-old toy. Two empty cans and some string. Hold the string taut and make some noise in one can. A person holding the other can up to their ear can hear it. My students also figured out that you can call "long distance" by joining two telephone systems together.
Tin Can Race
The tin can race demonstrated how mass, force, and velocity are all related. A small piece of plywood for a ramp, held up on one end by a couple of dictionaries, and some unopened canned goods of various sizes makes a good prediction activity. Students were supposed to roll the cans down the ramp and notice if size and weight had any affect on how far or fast they traveled. It was a popular station, but most of the little kids wanted to see how far they could **make** the cans go by pushing them. That wasn't really the science we were after, and we had to do some instruction on what a fair test is for kindergarteners and first graders.
A wool sweater and some party balloons was all it took to make this station a hit. The kids came and put on an old sweater, then they rubbed the balloons with their sleeves and made their hair stand on end with the static electricity. They had a great time pretending they were magnets.
I found an old plant light stand and a 20 ounce fishing weight. I hung the weight from the stand with a string, and the kids swung the pendulum around a bottle that we put on the floor. The kids noticed that the weight seemed to orbit the bottle, almost like a planet orbits the sun. They also noticed that it lost energy and eventually hit the bottle. They had fun counting how many revolutions around the bottle they could get from one swing.
You can make a vortex by taking two plastic liter-sized bottles, duct-taping their caps and drilling a hole through the caps. If you fill one of the bottles most of the way full of water and screw the caps back on to them you have something like an hour glass full of water. When you invert the pair of bottles and give the top one a little shake you can get the water to swirl around like a tornado. The kids all loved this station.
This demonstration illustrated resonance, and how similar objects would vibrate "in tune" with each other. I tied a string between two dowels mounted in a 2X4. Then I hung some machine nuts from strings of varying lengths, but paired so that each string and nut had at least one other one like it. I hung them (3 pairs) from the horizontal string. If you swing one of the nuts, the other one from the similar-length string will also swing. This demonstration, while it did work, took a fair amount of time to prepare, tangled up when it was moved from place to place, and did not **dramatically** demonstrate the phenomenon. What the kids (especially the youngest ones) tended to do was to swing the nuts vigorously and wonder what they were supposed to see. It took a bit more explanation and thought than some of our other stations.
The concept of friction, and I don't know what kind of motion (angular motion, maybe?) was the purpose of the spinning rings. We used some dowels and rubber washers. If the kids drop the washers over the dowel, the washers fall uninterrupted to the bottom of the dowel. But if you give the washer a spin, it takes considerably longer to make the trip. The kids figured out ways of getting the washers to move back "up" the dowel by suddenly inverting it.
Little paper helicopters were probably the most fun project we had. Interestingly though, at the carnival it wasn't all that popular. During our training day, I let the kids fly them from our high balcony in the school lobby. They had a ball but the acoustics in that room cause the voices to echo like a bus depot.
If you cut a rectangular piece of paper so that it has two "bunny ears," sort of, and bend the ears in opposite directions, the paper will twirl like a helicopter. In theory. Somehow, the kids managed to make all sorts of them that would not fly. I gave them plenty of paper and encouraged them to try to make LOTS of them to see what worked and what didn't. I got to see who was willing to learn from their efforts and which kids stubbornly tried the same faulty design over and over again. This activity gave me a lot of insight into the students' powers of analytical thought. And it was a lot of fun.
This activity was a way of "measuring" hand/eye coordination. Hold a ruler between someone's thumb and index finger. Drop it unexpectedly and see how many inches the ruler drops before they close their fingers on it. This is surprisingly hard to do when someone else drops the ruler. It's very simple when you drop it yourself.
Penny in a Cup
Penny in a cup is a demonstration of gravity, and inertia to a lesser degree. Place a penny on a card. Put the card on a cup. Then say that you can get the penny in the cup without lifting the card. Demonstrate by flicking the card with your index finger. The card flies across the room and the penny stays in the cup.
This was an amazing little demonstration about center of gravity. You need a hammer, a small bit of string, and a ruler. If you hang the hammer from the ruler in such a way that the head of the hammer hangs below a table's edge, and the handle of the hammer pushes up on the other end of the ruler, you can set the ruler on the edge of a table with only about a half-inch of ruler touching the table. It looks impossible.
This is a demonstration of a physical change, according to Tik Liem. But if you ask me it's also about conservation of matter. If you fold a paper in half and cut each half almost all the way across, in opposite directions, you can make a very big hole - a hole big enough to step through.
The marbles are a demonstration of force, as in MV=F. I used a Hot Wheels track and some large marbles. Line the marbles up on the track and roll one or two at the group. The same number are "bumped" from the other end of the train of marbles stuck on the track.
Stuck to the Wall
Stuck to the wall is a funny demonstration about center of gravity. You can not bend over and touch your shoe if you have your back to the wall to start with. Your rear needs to move back to balance your front, which ends up sticking out away from your center. If you can't send your rear further back, you from tip over. Just for fun, back up with your heels against the wall and try to tie your shoe!
Drops on A Penny
Predict how many drops of water one side of a penny can hold. Use an eye dropper to find out. This is a good demonstration of surface tension, and a great prediction activity.
Standing on Air
How powerful is air pressure? We put a garbage sack under a small piece of plywood. A bicycle pump was used to put air in the bag. This was fun for the kids. One got to stand on the wood. One got to pump. One had to hold the bag shut so no air leaked. The board cut the bag and the whole thing leaked more than it should have. So a roll of tape became necessary. I think they liked the pump, and didn't really mind that the bag didn't inflate. A lot of time was spent (by the kids) troubleshooting that one.
We used a water bottle and an eye dropper just full enough of water so that it didn't sink in a water bottle. Then I told the kids to hum and stare at the bottle. They did. I squeezed the bottle and the "diver" sank. They were clever enough to know that the humming didn't do anything, but it was fun to have them going for a few minutes. When someone asked me to set the bottle down so that they could tell if I was squeezing it, I knew they'd figure it out. Guess what?
Everyone seemed to have a great time at the festival. Some of the classes made us big thank you cards. My students learned a lot about presenting information, and they felt some responsibility for learning about the concepts that each station demonstrated. A few of them even rehearsed what they would say to their "customers." I think that there may be some younger students in the school who want to be in my fourth-grade class now.