Sunday, September 14, 2008

The Hexagon Hunt Begans - Updated

Last year the students spent a good deal of time working with pentagons. This year the focus is on the hexagon. Last week, the first full week of school, I began the first of a series of lessons I assembled over the summer. The lesson followed the same format as last year's introduction to pentagons. I laid out several rugs and on one I placed the hexagon shape from the geometry cabinet and two of the matching cards. I also placed the hexagon box.

I slowly pieced the hexagon together from the triangles within the box. I kept the lid on the rug beside it.

Next, I placed several hexagons cut from construction paper on the second rug. I pointed out to the children that they should be placed so that at least one side of two hexagons touched. After I placed mine, I distributed the rest to the students and called them one at a time to place theirs down.

The pentagon work last year with the construction paper shapes resulted in an almost spiral pattern.

The hexagon placement was a bonded assemblage. It appeared dense and stable. It lacked a sense of motion or fluidity. Instead the hexagon formation revealed what it is often associated with - construction, assemblage, fortification. I use these words as they are what come to my mind when I think of bee hives, hornets' nests and quilting.

On Friday, I performed a science experiment for the afternoon class: I began growing a crystal garden. I used ordinary rocks (ones with noticeable white stripes or deposits) and vinegar. The children sat motionless while I poured the vinegar over the rocks. They held their magnifying glasses in hand waiting to observe the rocks fizz from the vinegar bath.

Now, we wait for the sun to evaporate the vinegar and for the residue to form into crystals. The complete directions for the incredibly inexpensive science experiment are noted below. Please be advised that the crystals take several weeks to grow. Enjoy.

Crystal Rocks

To grow a crystal rock garden you will need a dish, a glass, vinegar and a handful of rocks of roughly the same size. Look for rocks that contain white streaks.

Pour a little vinegar into the glass. Drop one rock into the vinegar. If the rock starts to fizz remove it and place it on your dish. Put the rocks that do not fizz back outside. Pour vinegar over the tested rocks and into the dish until just the tops of the rocks are visible above the surface. Leave your dish in a sunny place and watch what happens over several weeks.

As long as it contains calcium carbonate - those white streaks - even an ordinary rock will sprout beautiful crystals. Vinegar reacts with the calcium carbonate in the rocks and starts to break it down. That is what makes the rock fizz. As the vinegar evaporates from the dish, tiny bits of calcium carbonate are left behind, clinging to the rocks. Over time. these bits join together and build up into lumpy aragonite crystals. To keep the crystals growing simply add more vinegar.

See: 101 Science Activities for Emerging Einsteins,
by Tracey Ann Schofield Teaching and Learning Company pg. 81

No comments: