This is our second year participating in a local science class co-op. Last year, I helped with the fourth and fifth graders, but this year, I am teaching the PK to third graders.
Our units of study will cover ocean life and chemistry. The mom who taught this class for many years before me has graciously lent me her lesson plans. For this, I am incredibly grateful, especially because I feel a little intimidated 'taking her place' as lead teacher. The lesson plans are wonderfully laid out and will be easy to follow. However, the year she taught these units, science co-op had two less classes scheduled. Figuring it would be easier to expand the ocean unit, I pulled together two lessons to add at the beginning of the school year.
The first class was an introduction to water. Since all of the children were familiar with water in general, we began the class by creating a list of "What We Know About Water." After listing many serious and silly facts about water, we moved onto some water explorations. These investigations were from Water, published by Evan-Moor Corp as part of the Science Works For Kids Series. Students learned about water taking the shape of its container, traveling to the lowest spots, and having surface tension. The pennies in the bowl demonstration was their favorite.
Next, we learned about the forms of water, including solid, liquid, and gas. The children labeled a worksheet. Using red arrows to represent heating and blue arrows to represent cooling, students decided how water went from one form to another. Then, using another idea from Water, I asked the children to pretend they were water droplets. Each student stood very still and very close to one another when they were ice (solid form). For water (liquid form) the students moved slightly apart and moved slightly. Spreading far apart and dancing, the students pretended to be steam (gas form). We then played a game. As the children continued to pretend to be water droplets, I held up a blue piece of paper. The blue represented cooling, and the children had to decide if they were to move closer and become still, or move further apart and dance. When I held up a red piece of paper they again needed to decide how to move. We played for several minutes moving through the three forms.
This activity easily led into an explanation of the water cycle. By reading This is the Ocean, by Kersten Hamilton, the children learned about water droplets traveling from the ocean to the air, over land, and down to rivers that travel back to the ocean.
We followed the reading with a water cycle demonstration I found in A Project Guide to Earth's Waters, by Christine Peterson. Having tried the experiment a few days before class, I knew it would work. The children could see water, a bit of fog, and condensation.
Once the water cycle demonstration was completed, I wanted the children to observe what happened when fresh river water flowed into salty ocean water. In another book from the library, I found the perfect demonstration. Awesome Science! Investigating the Secrets of the Underwater World, by Cindy A. Littlefield devised a easy to implement investigation. Tweaking the instructions a smidge, I made the salt water very salty to ensure success. Also, I had to use spring water and not tap, as Littlefield suggests. Our tap water did not work, as it is treated with too many chemicals. Once those alterations were in place, it was fascinating to watch the fresh water float on top of the salt water.
A small discussion on waves mixing fresh and salt water followed, and the class concluded with a summary activity of listing "What We Learned About Water."
I had hoped to end the class with a few outside water games as it was a hot day. Unfortunately, we ran out of time. Tomorrow, I'll share the second lesson.