By: Laura Newell, Cathy Youngblood, Michelle McCaskill
It is teacher friendly, but requires some planning and prep ahead of the unit to be the most effective.
Above all, it is extremely engaging for the students and allows for in depth conversation between peers on content.
Their scores, on the tasks and on their journal responses, were higher than any of the paper- and-pencil tests she had administered all year.
Using rubrics, students were able to see where their strengths and weaknesses were and discussion alerted them to the direction they may want to take on future performance-based assessments.
The Big "TAKE- AWAY"
2nd grade, Matter: Solids, Liquids and Gases
Rachel Ray, the famous chef from the Food Network, needs your help. A recipe she wants to include in her new cookbook calls for cornstarch to be added into the mixture. This seemed easy enough to her but something strange happened. She accidentally spilled some water into the cornstarch- the new substance she created was interesting, but now she doesn’t know how to explain its state of matter in her description. Help Rachel decide if her cornstarch is a liquid or solid by conducting your own investigation. Is it possible for this new solution to be both a liquid and a solid? – you decide! Students manipulate the mixture and record their answers to the following questions:
· Make a prediction. Is the new substance a liquid or a solid?
· What happens to the mixture when you let go?
· Do you think this mixture is a solid or a liquid? Why?
· Describe two ways in which the misxture is like a liquid.
· Describe two ways in which the mixture is like a solid.
· What is your conclusion? Why?
Can Salt change the temperature at which something freezes?
Performance Task: Have you ever wondered why people sprinkle a salt substance on their sidewalks, driveways, etc. when it's icy? What is it about salt that can change solid ice to a liquid? Can something change the temperature at which something else freezes? Explore with salt and water mixtures to see if you can determine if salt will change the temperature at which water freezes.