In Science Class . . . Week of 11/7

4th Grade: The 4th graders continued their exploration of electricity by finding out what materials conduct (carry) electricity and which do not. The students used a circuit board with a motor hooked up to a d-cell and put various objects between the wires. We also walked around the classroom to see which materials in the room would complete the circuit and turn the motor on.

• Which materials conduct electricity? (All metals - copper, brass, steel, iron, aluminum)
• How is this different from what materials are magnetic? (Only iron and steel objects can become magnets)
• What materials did not carry electricity? (Cardboard, paper, plastic, wood, fabric)

5th Grade: We had an exciting week! On Monday, students investigated properties of materials. We found that, unlike plastic or wood, metals can conduct (or carry) heat and electricity. We used the materials to complete a circuit and found that all metals will allow the motor to go on. We also put strips of material in a container with shallow hot water. The tops of the strips had butter on them. We watched as the copper and aluminum strips had butter that melted FAST! Steel and brass were slower. Heat was not conducted with the plastic and wood strips.

On Wednesday, we had visiting graduate students from the Cal chemistry department teach a lesson about chemical reactions and glow in the dark science! Students watched as they mixed two chemicals together to produce gas and light in a reaction similar to that which happens in a glow stick. Next, students mixed water, Elmer's glue and Borax to make a putty material. The material also had a little glow-in-the-dark paint which made it fun! Families, this stuff is not toxic, but please don't let your kids eat it! It will last for quite a while. If it starts to dry out, just add a little water. For optimum glow, re-charge the putty by exposing it to light.

• What properties make metals different than other types of elements on the periodic table? (Metals conduct heat and electricity much better than other elements. They also are mostly solid at room temperature and won't break when hammered into thin sheets. These properties make them extremely useful for building things)
• In the two experiments with the grad students, how did you know a chemical reaction occurred? (In the first one, gas and light were produced. In the second reaction in our zip bags, the material turned from a liquid to a solid with the addition of the liquid Borax solution. This unexpected phase change is often indicative of a chemical reaction.)

PLEASE: If you have any old food or household packages or bags (that aren't gross) that have the ingredients listed on them, send them in with your student for class on Wednesday, 11/16. Anything would be great - chip bags, cereal boxes, bread bags, toothpaste boxes, soda cans, etc. We'll be looking for elements on the package. Cereals are especially fun since there are often minerals added for nutritional value like iron, zinc etc. Thanks!