How Much of the Earth's Water is Fresh?
Students began the lesson by examining fractions and percentages. We used a piece of paper to represent saltwater and freshwater by dividing the paper into smaller and smaller pieces.
Next, we observed salt crystals by tasting them, looking at them with our eyes, and looking at them under a microscope.
We explored other minerals as well, classified them by attributes, and learned how rocks are formed.
Experimenting!
Our essential question of the day was: how does salt get into our oceans?
Using inquiry, students made predictions and created a simulation of the water cycle.
First, students made "land" from sand and rocks at the top of a paint liner. We discussed elevation and the meaning of the term "sea level." Then they collected "rain" in a "cloud" (tap water in a cup). They made observations about the rain and assured me it was freshwater.
Next, students poured the rain onto the land at the top of the liner. As the water flowed, it created a river, which collected at the bottom of the pan. This water was our "ocean." Students tested the ocean water - it was salty and looked like it had lots of minerals!
Can you figure out how that happened? Your second grader is sure to know!
PS: Did you know that there is GOLD floating in our ocean water, too?
Think of that next time you get hit by a large wave at the beach!
