Monday, September 09, 2013

Characteristics of Living Things

Living things to observe
and jump start thinking.
 As an introductory activity to my ecology unit, I wanted students to start thinking about what makes a living thing living. To aid with the brainstorming I provided them with a live plant, a preserved animal (but told them to imagine it as living), and a packet of seeds. What characteristics, processes or needs did these three items possess that leads one to know that they are living? As you can see from the list on the white board they came up with quite a few ideas. Each year I get a different list of things. When the students are having a good day I get really complex answers like: reproduction, die, make waste (feces or urine), are made up of cells, require or consume energy, grow, require nutrients, need water, use oxygen, and the list goes on.

Once that list is generated we work on looking for commonalities between the three items in order to generate a list that all living things have. That list is generally smaller since not all living things have blood or eyes. My next step is to introduce the concept of biotic and abiotic factors. This allows us to build up the necessary vocabulary for studying the components of an ecosystem.
Lists of the characteristics, processes,
and needs of living things.

Thursday, September 05, 2013

Observations vs. Inferences

On the opening day of each new school year I get students thinking about the steps of the Scientific Method. Of course all science begins with observations. I show them the following item.

Observation bag

I hold up the bag and walk around the room showing it off, even making sure they get a view of the bottom of the bag. With a student at the white board to act as a scribe, I begin to solicit observations of the bag. Students say the following: brightly colored, pink, yellow, green, has flowers, has designs, there's a ribbon, there's a handle, there's white tissue paper inside, and the list goes on. Sometimes it's difficult to get the flow of ideas going but once someone starts it tends to get easier.

Eventually one student may make a comment like: "It's a present" or "It's for a girl." That's when I can discuss the differences between observations and inferences. Because we've had previous experience with something when we observe something new we filter our ideas through those experiences and draw conclusions. It's an opportunity to discuss how our culture influences our inferences. What if we lived somewhere where pink items were not associated with femininity?

Third step, ask students if they have questions about the bag. I usually get: what's in it, is it heavy, is it a present, who is it for, etc.

I ask for a volunteer to come up and put their hand in the bag and using only their sense of touch describe the object. They usually know what it is but are not allowed to say so to the class. Then another student is invited up to look in the bag and give only observations of what they see. I will let the class begin to ask questions of myself or the other two students, that is besides the obvious - what is it. After a few of those are answered someone usually gets the answer. And there you go in a quick, easy activity the students have been introduced to the scientific method.


Mystery item inside