The reason was that I was preparing for the lab for this week, which is an acid/base titration. A titration is done to determine the relative strength of an acid or base. In our case, we slowly added NaOH to HCl and kept track of the pH through each 2 mL added. The W section did this today. The first halfgroup did well, but I tried explaining it all at once instead of doing it in steps. With the second group, and Mrs. Nolan's help, I succeeded in helping them get done early and done well. It is a great lab, but the setup is massive. I spent a total of three hours setting things up, and I still have to reset up the lab each time we do it--at least a 10 minute job itself. But for the students I teach at L-S, there is nothing I won't try to get my job done well.
The S, O, and L sections got to head back to the molecular model kits one last time, building some hydrocarbons this time, the hardest being C2H2. Many of them succeeded, and though it was noisy it was very productive. Students were helping each other, which always warms my heart. I handed out lots of OWLSbucks for students who were concentrating hard and getting the job done.
I also showed the students how liquid indicators worked for acids and bases, and physically showed them what neutralization is (mixing an acid with a base to reach a pH of 7). At the end I did a demo of elephant's toothpaste which involved a 30% solution of hydrogen peroxide, soap, and food coloring. Ask your son or daughter about it; I'm sure they will remember.
Here is a picture of the team teachers to brighten up your day, or sadden you, depending on your current state of mind.
Notice that we are spelling "OWLS" with our fingers.
Sweet justice.
