Tuesday, February 18, 2014

Matter & It's Changes

The first and second grade students at Joseph Gale began their winter trimester STEM unit on Matter and It's Changes. Teachers started with a preassessment on matter to find out what students knew about objects that were made of matter, what matter looks like in its three phases, and the types of changes that can happen to matter when exposed to heating and cooling. Here are some examples of what the preassessment looked like:
Here teachers were trying to find out if students knew that most objects around them are made of matter. Also, they asked students to draw pictures of the three states of matter: solid, liquid, and gas to see if they knew that particles have more space in between them as a substance moves from the solid to the liquid and eventually to the gaseous phase. Modeling is very important in the Next Generation Science Standards (NGSS) and when we are explaining something that is too small or too large to observe with the naked eye, we need to make models to help us explain how and why something happens.

Many students left these boxes blank and did not know what these words were describing. A few students mentioned that they know the word matter from asking someone, "What's the matter?" and then drew a cartoon describing a scene where they notice someone is upset and asking them this question. This is a reminder that words that are used in science often have different meaning than how we use them in everyday life.

To explore what is made of matter and the three phases it can exist in students,  have spent their first week watching videos, reading poems, classifying items they observe, and reading books. Here are some of the resources used in the classrooms.

Poems on Matter:


Videos on Matter:
Here is one from the Massachusetts Institute of Technology (MIT) on "What is Matter?"
MIT What is Matter?

Bill Nye: Phases of Matter
Phases of Matter

Here is another using magnetic marbles to show the three phases of matter:
Magnetic Marbles model the three states of matter

Books on Matter:

Categorizing Matter
While second graders made a list of what items they could observe around them were solids, liquids, and gases (pictured below) first graders looked at pictures that were cut out from magazines and made a collage of solids, liquids and gases.

Modeling Matter
At the end of last week, students were making models of the three phases of matter by drawing solids, liquids, and gases in second grade and using Cheerios to make models in first grade (pictured below). Students also indicated if the change between phases was caused by heating or cooling the substance.


In this assessment teachers were trying to find out if students knew the difference between a change in matter that can be reversed or a change that is more permanent due to heating and cooling. This addresses the second grade NGSS standard "2-PS1-4. Construct an argument with evidence that some changes caused by heating or cooling can be reversed and some cannot." and is the main area of focus for their unit. 

Most students responded that water could be turned back into ice but we need to be cautious here. We give the names "ice" and "water" to describe different phases of the same substance-H2O. While "ice" is used to describe the solid phase and "water" is used to describe the liquid phase, they are both still H2O. Some students might think these are different substances so this would make for a great dinner table conversation or home experiment to see what happens when we freeze or melt water. Most students didn't think that you could turn a cookie back into the dough it came from but the reasoning was that they eat the cookie and it gets digested. Next, time you are making cookies it might be interesting to put one in the freezer and see if it turns back into dough from cooling down. Last, there was much confusion and conversation over the burning log turning into ashes and the butter melting. Many students were convinced they could reassemble the ashes back into a log by cooling it and they weren't sure about butter. Perhaps this is because although we cook with it often, it gets incorporated into our food and they never see what happens when it cools back down. Next time you are making smores together as a family, take a moment to talk about what changes can go "back and forth" and which ones can't. I think you will find there are examples of each to discuss. 

Stay tuned for the cookbooks students will be creating as they explore the world of reversible and irreversible changes!