Minerals: From Observation to Definition

On the first day of our mineral unit, I have students spend the period observing 12-15 different minerals.  The minerals are each accompanied by an index card with the mineral's name on it. 

Students must write down 3-5 (depending on the students) observations about each mineral: state of matter, color, shape, shiny-ness, etc.

For homework, I have students use their observations to draft their own definition of what a mineral is.  They're looking for things that all of the minerals they observed have in common.  At the very least, they should get "solid" as part of their definition.

I then have them look up the textbook definition and we proceed from there.