Tuesday, January 24, 2012

In Science Class . .. Weeks of 1/16 and 1/23

5th Grade: Last week and this week, we've continued our study of evaporation. Students put the same amount of water in different sized containers (with different surface areas) and measured how much water evaporated over the weekend. We found that the containers with the most surface area (water spread out) had highest evaporation rates, while our tall, thin vials barely lost any water to evaporation. Next up, we'll be looking more closely at the atmosphere and water cycle.
Key questions:
  • What did your group find out about evaporation? (Evaporation happens more quickly in areas with higher temperature and in containers with larger surface area)
  • What process is the opposite of evaporation? (Evaporation is the process of a liquid changing phase to a gas. Condensation is the process of a gas turning to a liquid. Freezing is liquid to solid while melting is solid to liquid.)

4th Grade: Last week, we examined the mineral property of hardness. Student experimented and found that "harder" minerals can scratch softer ones. We scratched four minerals with our fingernail, an aluminum nail, and a paper clip. The hardest mineral, quartz, could not be scratched by any of the tools, while gypsum, the softest, could be scratched by all three tools. This week, we discussed the Mohs Hardness Scale, which ranks minerals on a scale of 1-10 based on their hardness. Gypsum was a "2" while quartz was a "7." Often times, gemstones like emeralds, rubies, etc are high up on the hardness scale. Diamonds are a "10."

  • What minerals were softer? How did you know? (Gypsum and calcite were softest and could be scratched by at least 2 of the tools. Fluorite and quartz were harder and couldn't be easily scratched.)
  • What mineral was the hardest? (Quartz was hardest and could not be scratched by anything. FYI, it's a "7" on the Mohs hardness scale.)
  • As we look at the hardness scale, can a "3" scratch a "5" mineral? What about the other way around? (A "3" mineral cannot scratch a "5" mineral because a "5" is harder, but a "5" mineral can make a mark on a "3" mineral.

Tuesday, January 10, 2012

In Science Class . . .. Weeks of 1/3 and 1/9

5th Grade: This week, the students will be focusing more on evaporation and recording data. We will examine our paper towel experiment, and then design an experiment to investigate how different locations in the room affect evaporation. Key questions:

  • What happened to the scale with the paper towels? (The paper towel without the lid dried, meaning the water evaporated. The paper towel with the lid did not dry because the water was contained, though there was some condensation on the inside of the cup. The scale tipped toward the side with the lid because it still contained water, whereas the water on the other paper towel had escaped into the atmosphere.)
  • Where did your group place the cups with water? What predictions did you make? Which cups will have the highest evaporation rates?


4th Grade: Our new unit is on earth science. Last week, we examined some fake and real rocks and discussing what sort of information geologists collect. Students will be working with the measuring tape and balances to collect data on the circumference, mass and diameter of their rocks.

  • What sorts of information do geologists collect when they study rocks? (They look at the size, shape, texture, location, color, luster, etc. They also will weigh and measure the rocks)
  • What did your rock look like? What did you notice about your rock? (Most of the fake rocks are gray with green and blue "minerals.")
  • What tools did you use to collect information? (We used a measuring tape for circumference and diameter. The unit of measurement being centimeters. For the mass, we used a balance and took the mass in grams.)

This week in science, we acted like geologists and broke apart our fake rocks to see what "minerals" were inside. The students were able to identify several different ingredients, including red and green gravel, shells and some gray material. We then used water to see if we could separate the gray material. Key Questions:

  • What is the difference between a rock and a mineral? (Minerals are the ingredients of rocks and are just one type of substance, while rocks are made of many types of minerals.)
  • What types of "minerals" did you find in the "mock rock" Ms Jenkins made? (Most groups will find red and green gravel, shells, and gray material that we separated with water)
  • What do geologists do? (They study rocks and make observations about the shape, size, texture, color, shininess, mass.)
  • How are rocks and minerals used by humans? (We use them in various mixtures for roads, houses, jewelry, etc)