Below is what we did to complete the Home Scientist Badge. We did the last three steps at our fall camp out (the girls adored the mentos geyser and the dinosaur snot), and the first two at our last meeting (bending water was also a hit).
The next time I do this badge, I will choose making ice cream for the kitchen chemist, and will probably make a density tower from Steve Spangler Science instead of using one of the options in the book.
1. Be a kitchen chemist
—> Make salad dressing. We made salad dressing since I had all of the ingredients on hand. I did modify the experiment slightly in that I gave each girl a baby food jar to put the ingredients in. Each girl put what amounted to 1/4 of the amounts called for in the recipe into her jar. Before I let them mix the dressing, I explained about the varying densities of the mustard, vinegar, and olive oil. I also explained what an emulsion was. Then we put the lids on, and the girls shook the jars as hard as they could. Each one had to try a taste of her dressing (I passed around some baby carrots). The girls enjoyed the process, but not so much the tasting.
—> Make butter. Next time came, and we made butter! I followed the directions in this video, and the girls had a blast. Butter is now the way for me to go with this badge in the future.
***Next time, I will do the “make your own ice cream” option.
2. Create static electricity
—> Bend water. I gave each girl a small, black comb to brush their hair with. Then they held it almost touching the stream of water. This was definitely a hit with the girls. They loved watching the water bend.
3. Dive into density
—> Egg in salt water. This experiment worked, but it didn’t have a WOW factor like the ones from Steps 4 and 5. Don’t worry if there is a layer of salt at the bottom of the glass. The ratio of salt to water oversaturates the water. The egg did float, but we didn’t have the clear the demarcation between fresh and salt water that the instructions said we would. One of the moms filled another class from the tap so we could put the egg in there to show the difference between fresh and salt water.
—> Lemons vs. limes. It was interesting, but we had a dud lime. Both lemons floated, but one lime sank and the other floated. I tried to make sure all four fruits were as close to the same size as possible. We also peeled the fruit to see what happened if the rind was removed. The lemons still floated and both limes sank. Steve Spangler gives a more in-depth explanation about what’s going on.
4. Make something bubble up
—> Soda geyser. The girls absolutely loved it! You definitely need to put the mentos on a piece of tape before you drop it into the bottle. However, we did it twice and neither time was I able to get the whole tape of mentos into the bottle. It started fountaining once any mentos hit the soda. Both times, the soda shot up about 2-3 feet into the air. The record is 18 feet (per Steve Spangler). I think I’m going to buy the Mentos Geyser Tube and try it again at one of our meetings. Also if you want a more in-depth description of what’s going on, check out what Steve Spangler has to say. And this is a neat video by two guys with too much time on their hands.
5. Play with science
—>Dinosaur snot. Again, the girls absolutely loved it! I would allot 30-45 minutes for this activity since the girls should want to mess around with the goop once they’ve made it (poured into small, individual bowls). We made two batches – one lime green and one purple. It can be a bit tricky to stir since the cornstarch and water do not want to mix. Also, when it comes time to dispose of it, do not pour it down the drain!! Put it in a ziplock baggie and then in a trash can. Because of how the cornstarch and water interact, it can cause the drains to become clogged.