Early lessons in attraction

I'm suddenly wondering what all I did as a kid that made my teachers question my level of intelligence.

In 3rd grade Mrs. A gave us an extensive lesson on magnets and magnetic attraction.  Then she took us outside with a large, over-sized magnet and let us take turns picking things to test for being magnetic.  All of the other kids picked things like a nail or a paperclip from the ground (yeah, I don't think our school had the safest grounds) or the iron railing for the stairs.  Me?  I brought her a rock.  Every time.

But this was my reasoning:  I knew how magnets worked.  I wasn't interested in confirming what I already knew - that the magnet was going to attract a paper clip or anything obviously metal like that.  She had mentioned in the lesson that magnets were attracted to metal and that the metal was found in the earth, in rocks.  So duh, I wanted to find some hidden stuff I couldn't obviously predict... it was like a random treasure hunt.

I'm pretty sure all Mrs. A thought was, "Oh great, here she comes again.  With another rock.  Did this girl listen at all?  I've already told her that probably none of the rocks her have iron in them.  Seriously, they put this child in gifted and talented?  They must be desperate."  As I came at her with a big stupid smile and another large rock in my hand.

We never did find one that attracted the magnet.