September 3, 2015 by WittyLibrarian
Target Age Range: Families
Program Length: 90 minutes
Brief Description: Hands-on activities with messy, splashy science experiments.
Snack sized Sandwich Baggies
Tablespoon measuring spoons
Container to hold filed water balloons in
2 long, narrow and shallow plastic storage containers
2 tinfoil roasting pans
Hula Hoop covered in yarn
Bubble solution (enough to fill bottom of pool and separate container)
Container to hold bubble solution
16oz empty plastic soda bottle
20-volume hydrogen peroxide (20-volume is 6% solution, purchased from a beauty supply store)
Dawn dish detergent
Foil cake pan with 2-inch sides
Empty water bottles (12 oz or bigger)
- Make Oobleck
- Prepare bubble solution
- Using duct tape, secure PVC pipes to all but one open bottle of Diet Coke
- Cover hula hoop with yarn
- Fill water balloons
- Print out instruction signs
- If making Bubble Snakes, cut microfiber cloth into small squares and cut out bottoms of water bottles.
Note: Although this program can be done on a small scale, we usually present it to a crowd of 75+ participants.
2. Demonstrate Elephant Toothpaste
3. Demonstrate Coke and Mentos
4. Break participants into four groups and rotate among four stations
– Exploding Sidewalk Chalk
– Water Balloons
For the demonstrations, we presented them to the group as a whole. We performed the experiments while explaining the science behind each demonstration.
- Demonstration 1: Elephant Toothpaste
The chemical reaction this experiment produces is very foamy and fun, and was a real crowd-pleaser. We used the instructions and explanation from Sciencebob.com for our experiment, but Stevespanglerscience.com also has a useful write-up. While performing this experiment, the presenter wore safety glasses as a precaution.
- Demonstration 2: Coke & Mentos
This is the classic, messy science experiment. Most everyone in the program had done
the experiment before, but they still loved seeing it. While explaining the science (here, here, and here for various explanations), we demonstrated with one bottle of Diet Coke. After the first Coke and Mentos experiment, we asked if everyone wanted to see the experiment again. When we received a very enthusiastic “Yes!”, we brought out six bottles of Diet Coke, to do the experiment on a bigger scale.
In addition to using six bottles of Diet Coke, we attached pieces of PCV pipe to the top of each bottle of Diet Coke. We were inspired by this set of Instructables, although we did not make the device described. We found that we could attach a PVC to the bottle of Diet Coke with duct tape and it worked well for our purposes. You can also buy Geyser Tubes from SteveSpanglerScience.com. With the help of some volunteers, we did a coordinated Mentos drop on the count of three.
A word of advice: Run, and run fast, once you drop your Mentos, especially if using the PVC pipe. You will get a Diet Coke shower, otherwise!
For the stations, instructions were displayed for families to follow together. We also had either a volunteer or librarian on hand at each station to assist families as needed.
- Station 1: Exploding Sidewalk Art
We adapted instructions found here and here for this experiment. Depending on the size of the bags you want to pop, you might have to vary the quantities of cornstarch, baking soda, and vinegar used. For our program, we used snack-sized sandwich bags, and had to experiment to find the perfect popping amount. See our handout for exact quantities needed.
Additionally, we found it best to have participants mix the vinegar and cornstarch
together first, before pouring it into the bag, otherwise the bag would break during mixing. We also found it useful to have the bag half closed before tossing the baking soda pouch in; this allowed enough time to close the bag before the reaction started.
- Station 2: Water Balloons
We had the water balloons pre-filled and stored in a giant tub. Each participant could use up to three water balloons, and test how a water balloon could be thrown so as not to pop.
- Station 3: Oobleck
For the Oobleck station, participants had two ways they could interact and experiment with Oobleck. First, we had two tinfoil pans of Oobleck that people could explore with their hands. Second, we had 2 long containers laid out on the ground for participants to run across (after they took off their shoes!). The nature of Oobleck is such that if a person runs across it, they will not sink; if they stand still, however, they will sink as if in quick sand! We kept wipes by this station for participants to clean up after playing in the OObleck.
A note regarding making the Oobleck: although specific measurements are given to mixing Oobleck in the instructions, we found it best to mix the Oobleck by hand, starting with a base of cornstarch and gradually adding in water until it was mixed to the right consistency. The right consistency is obtained when you can smack your hand into the Oobleck and it doesn’t splatter, but your hand slowly begins to sink if left in place.
- Station 4: Bubbles
For the bubble station, we had two different activities to try. For the first one, participants could attempt to stand inside a giant bubble, using the kiddie pool and hula hoop. We found that covering the hula hoop with yarn allowed more surface texture for the bubble solution to cling to in order to make this experiment more feasible. It also helps to have participants stand on a stool while inside the bubble, to ease surface tension.
The second bubble activity has varied. The first time we presented this program, participants made bubble snakes, according to the directions found here and here. The Bubble Snakes worked very well, but despite frequent reminders to both children and parents, some children had a problem remember to breath out with the Bubble Snakes, not in, and thus had a mouth full of bubbles. The second time we offered the program, we had participants make their own bubble wands out of pipe cleaners, straws and yarn.
Fantastic Foamy Fountain by Sciencebob.com
Elephant’s Toothpast- Kid’s Version by Stevespanglerscience.com
Mentos Diet Coke Geyser by Stevespanglerscience.com
The Science of Coke and Mentos by Eepybird.com
Why Do Diet Coke and Mentos React? by Daven Hiskey on Mentalfloss.com
Mentos Geyser Tube: re-Make by chrismake on Instructables.com
Geyser Tube on Stevespanglerscience.com
Exploding Sandwich Bag Experiment by Cometogetherkids.com
Play Recipe- Sidewalk Chalk by Crystal Underwood on Growingajeweledrose.com
Science Projects With Water Balloons By Alice Ladkin on eHow.com
Oobleck: The Dr. Seuss Science Experiment by fungus amungus on Instructables.com
Giant Bubble Experiment by Stevespanglerscience.com
Rainbow Bubble Snakes by Housingaforest.com
Bubble Science by Science World on Education.com
How to Make a CO2 Sandwich by Stevespanglerscience.com
Oobleck – a Non-Newtonian substance by Imaginationstationtoledo.org
Bubble Snakes- Bubble Blower by Stevespanglerscience.com
Try This: Water Balloon Toss by Tom Robinson
Balloon Toss Lab by The Physics Classroom
What we would do differently:
The experiments in this program all went off extraordinarily well, with the exception of the Bubble Snakes. As noted above, we had trouble with children breathing in the bubble solution, rather than blowing out when trying out their new Bubble Snake. We did issue constant reminders to blow out, not in, and took extra care to inform parents, but it still happened. Thankfully, our bubble solution was non-toxic and merely tasted bad. However, to prevent this happening again, we have since adapted the program and eliminated the Bubble Snakes. In its’ place, we had children create their own bubble wands using pipe cleaners, straw and yarn.
Adaptation for older/younger audience:
As this was a family program, it was designed to work well with all ages. The various experiments can be broken down and used in other programs.