I love my job as a technology resource teacher. But, sometimes I’m invited to teach in the classroom. After they recently completed a science unit on matter, I informed the second grade that I would be visiting their class and we’d perform an “investigation” about the states and changes of matter. Of course they were excited. Kids love to investigate, manipulate, and create. One student asked, “Can we please mix things? I love pouring and mixing!” 😀
BACKGROUND: First, we did a quick review of the properties, states and changes in matter. I left a visual up on the interactive whiteboard for reference. Before starting the investigation, I told them that we’d mix a liquid and a solid together three separate times and that I wanted them to pay close attention to whether the result was a physical or chemical change. I had students write a hypothesis: What do you think will happen when you mix the baking soda (solid) to one of the liquids?
INVESTIGATE: Students eagerly measured and poured 1/4 cup of water (liquid) into the first clear plastic cup. Then, they scooped and added two heaping spoonfuls of baking soda (solid) and then stirred. What happened? “It’s cloudy.” – “I think it’s turning into slime!” – “Hmmm. Is this a solid?” They wrote their observations down. Next, they mixed milk and baking soda. Still very liquid. A couple of them noticed that the baking soda and water mixture was starting to thicken up.
OBSERVATION: Last, students measured and added 1/4 cup vinegar to the third plastic cup. Then, they added the baking soda. Immediately they shouted with delight as their mixture bubbled and sizzled up! They knew that the bubbles was a sign of a chemical change. We discussed how the solid (baking soda) and liquid (vinegar) reacted to form a gas (carbon dioxide & sodium citrate), causing the liquid to fizz and bubble.
Second grade had so much fun – and made a mess – but it was worth it to see how excited they were and to listen to their remarks and observations! I’d be honored if you hopped on over to my TPT Store, Seashore Scholar where you’ll find another fun activity: F-R-E-E STEM Marshmallow Challenge!
