So I had so much fun with the high school acids and bases lab last week I decided to do a simpler version with the middleschoolers today. I actually found an old keynote presentation on acids and bases that I had made a few years ago so I showed that to the kids in the beginning of class. It mainly pointed out why acids/bases are important, how changes is soil pH can affect plants, acid rain and its affect on trees, lakes, fish and even statues. It also had a few slides on pH levels in the human body and our blood is very picky about its pH level and small changes can make you sick or even cause death.
I also showed these two videos before we started the lab.
I didn’t show this one in class but the last slide of my presentation mentioned these whip scorpions shoot acetic acid for self defense. Here’s a slow motion video of them doing just that.
I bought an interactive notebook lift the flap thing on acids and bases from teacerspayteachers (Bond with James) because I was too lazy to make my own and it was only a few dollars. You can see it in the lower left of the photo below. I also gave the kids a photo of cabbage indicator for different pHs to compare with their solutions. I made the blank test tubes you see on the right page for kids to color and record the pH value for various household items.
As you can see in the following photo, the students got a wide range of colors. These 50ml centrifuge tubes worked great for this lab because they’re big enough that pouring into them isn’t as difficult as a narrow test tube and they have measurements on them so it was easy for them to put roughly 15ml of cabbage indicator into each one.