Science in the Library

Last week I visited the Hastings Branch of Pasadena Public Library to present a program to their "STEAM Team," a monthly club they have for kids 9-12 years old. We did a program about electricity called "Make Your Own Electric Quiz." It was so much fun exploring the mathematical principles involved in electrical circuits, such as the inverse ratio relationship between voltage, resistance and current explored by Georg Ohm in the early 19th century. I LOVE anything to do with scientific laws, and we got deep into Ohm's law (I = V/R). Then kids wrote down math questions and answers on post-it notes, placing the post-its next to some brass paper fasteners I had prepped for them on a sheet of cardstock. On the other side, they wound a copper wire from the brass fastener for each question to the brass fastener for its correct answer. To reinforce the things we learned about Ohm's law, I deliberately used a battery source not intended for 5mm LED diodes--...

On August 8th, we had a packed story room full of kids 7-12 years old who were here to learn about how electricity works, what kinds of materials conduct electricity, and how to make their own batteries. First, we viewed a slideshow that explained concepts like electric current (the movement of electrons from atom to atom) and the history behind the making of the first battery in 1800 by Alessandro Volta: Make a penny battery from AnnMarie Ppl Then I gave everyone an envelope with some squares of matboard (like what artists use as the backing and framing for prints and drawings), an LED diode, and five pennies, two of which I sanded for each child in advance of the class. The kids had to sand two more pennies and leave the 5th penny alone, while letting the squares of matboard soak in some kind of solution. Why sand the pennies? Because all pennies made after 1982 are made with mostly zinc and just a little bit of copper. Sand the copper off of one side, and you n...

On May 19, 2017, kids came to the Pasadena Public Library to make wind turbines that would generate electricity by turning the shaft of a hobby motor. We were inspired by a project we found at https://www.exploratorium.edu/snacks/light-wind . The goal was to use the motors in reverse--instead of the electricity making the shaft turn, the turning would make electricity! We hoped to produce enough energy to light an LED bulb attached to the motor. It didn't work out that way, but we still made a great science lesson of it. I provided several different motors, but every time I tested them myself, I could not get the LED light bulb to come on. One kind of motor I got at Fry's was just too strong to turn in the wind. It probably would have needed blades several feet long and a floor fan wasn't going to produce enough wind. The other kind turned easily , but didn't generate quite enough voltage. (One of the kids accurately noted: "Don't you need more energy to op...