Digging into density

Danielle McCune of Springboro Junior High attended the Geology workshop and led her 8th grade science class through several of the lessons. She shares about their experiences.

"I started this unit with a demonstration of density using ketchup packets. We talked about the controlled variables and why one might float while the other sank. This discussion led to the students concluding that one packet had an air bubble and how that air affected the packet of ketchup.

"The students knew the term density but were not sure exactly what it meant. We went through each part of the formula for density, D= M/V. We talked about the difference between weight and mass and completed some density math problems.

"The next day, we completed the Differentiation of Earth’s Layers activity. I did tweak it a little by using beakers and different liquids. The students predicted what they thought would happen when the three substances were placed in the beaker. Quite a few students still thought that they would mix into one liquid. We drew pictures of our predictions and of the actual results. The students concluded that the most dense material sank to the bottom of the beaker and that the substances did not mix because their densities are different. The students also looked at the Ohio crude oil sample given to me at the workshop and we discussed the density of the oil and what oil crude oil could be used for.

"Through our discussion, the students inferred that the way the densest materials sank to the bottom of the beaker relates directly to the most dense material going to the center of the Earth. We then read, took notes, and made a foldable of the Earth’s Layers for the students to increase their understanding of each layer. To conclude this lesson, the students took a couple of days and completed the Scaling Out Earth’s Layers activity. This allowed them to see the relationship between the size of each layer at a scaled level."

McCune said that both activities went very well, as the students were engaged and actively learning.

"I enjoyed the OOGEEP workshops a great deal. This was my first experience attending a Science workshop. Everyone was very friendly and knowledgeable. They made me feel like a true science teacher and allowed me to gain from their knowledge and experiences," McCune said.