Where Does One Get a Petri Dish in Dallas?

Perhaps you are like me. Perhaps you have school-aged children whose science fair projects are due — soon! Perhaps you are wondering what experiment you are — I mean, your kid is going to do. And perhaps you just learned, as I did, that the Science Projects Store on TI Boulevard is closing its doors for good this Friday and is sold out of petri dishes (and other materials).

So, uh, where would you go to find petri dishes and agar?