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# Magnetic Dirt?

Who knew?  There are magnetic materials in dirt.

I have been doing a unit with my third grade students about magnets.  We have been learning about the properties of magnets such as attraction, repulsion, and polarity.  In one of the extension activities, students are required to place magnetic filings over a magnet to see how the magnet has north and south poles. Immediately I thought of the little games with the bald man and magnetic pen in which you drag the filings over the man’s head to give him hair.  I thought, “Oh!  I could buy several of those and cut the plastic to get iron filings!”

Then, when looking for one of these “Wooly Willy” games on the internet, I happened across a You Tube video about finding iron in dirt.  I didn’t really think it would work, but…….

here is what a couple of kids found after school when I made sure this would work.  Now, we didn’t do it exactly like the video.  I gave the kids a stack of strong disc magnets which I purchased form Hobby Lobby for about \$7.  They put the magnets inside a plastic bag.  When they rubbed the bag in the dirt, the magnets attracted no iron.  What did work was for the kids to put the dirt in a container which they collected from under some trees.  They brought the dirt inside and sprinkled it a spoonful at a time on the plastic bag with magnets inside. Then when they shook the bag off onto some construction paper, the magnetic particles stayed.  They emptied those pieces into a petri dish, which you see above.  Sidenotes:  In our case when the dirt was damp from some rain, this method worked best.  At first they collected dirt from underneath some gravel in a garden.  I thought it wouldn’t work because that dirt didn’t appear to have any magnetic properties.  It wasn’t until they collected the dirt underneath the trees that they found the iron particles.

Now instead of buying iron filings, I am going to let the students find their own before we do our polarity experiment.  I think they will very much enjoy the trip outdoors!  Even though it is January, it has been 70 degrees this week.

Here’s a great tutorial about magnetic polarity!