Safety First! (And now my kids believe me!)

Something I won't budge on in my science classroom is the issue of safety.  My kids wear goggles more often than not, and we regularly discuss applicable safety rules before almost every lab that we do.  My middle school students don't like to follow the "Always wear safety goggles" rule.  (They'll mess up my hair! Are these leaving lines on my face? Do I look weird in these? yada, yada, yada...)  After what happened today during 8th period, though, I don't think they'll question me on it anymore! ...

I set up a convection demonstration on one of the front lab tables.  It was simple, and one that I've used twice a year for probably 6 years or so.  I brought in a large 10x13 Pyrex baking dish from home, filled it with water, and then set it up so that one half of the dish was on a hot plate, and the other half was just resting on some books that I had stacked up.  Once the water gets heated up enough, I can add red food coloring to the hot side, and blue coloring to the cooler side, and we can watch convection in action!  However, as the water was heating up (the students were still in their seats working on making a foldable) suddenly the entire Pyrex baking dish EXPLODED!  Literally... exploded.... !!!!  We all jumped a mile, and I'm pretty sure a couple of the students screamed, simply because it took us all off guard!  There was glass everywhere.  I found glass in about a 7 foot radius around the hot plate!  And I'm not talking big chunks of glass; I mean the itsy-bitsy tiny shards of glass that are nearly impossible to see.

I took the opportunity to explain to my students who witnessed the event why it is always so important to wear safety goggles when working with hot plates, even if it's just water in the beaker.  I make them wear goggles because I want them to stay safe for the 40 minutes that they're with me every day!

I cannot tell you how thankful I am that no one was injured as we were not observing the demonstration at the time of the explosion.  Aside from a good amount of time spent cleaning the tables and floor, and now needing to buy a new baking dish for home :), all is well. 

Rachel