GRANTED WEDNESDAY was a mean September steamer, but why were all those public schools so quick to throw in the towel and close down? Heat of that kind is no reason for sending away legions of children. To make matters worse, some of the local systems caught parents unawares, announcing shutdowns in mid-workday and in many cases failing to notify them. You have to wonder what's more dangerous--a stuffy classroom of uncomfortable students or thousands of elementary schoolchildren trying to get home safely?

School officials point out that they're caught in a damned-if-they-do-or-don't situation; some parents will accuse them of child abuse almost any time the temperature and humidity rise in tandem and schools stay open, while others point to their own childhoods with romantic recollections of braving all elements in the name of Being There. Come to think of it, we do remember back a long time in this area to days when air wasn't conditioned and people were. True, at certain hideous temperature levels, adults in government offices downtown were granted relief from full workdays. But school was a more relentless event.

There were some genuinely intolerable cases on Wednesday, including temperature readings in some classrooms of 103 degrees, and some buildings in which air conditioning broke down and windows weren't built to open. Also, because schools were barely open for the year, many of their offices had no up-to-date contact sheets to notify parents.

But these decisions to close down--which, unlike snow situations, do not involve travel conditions-- should be made on a school-by-school basis, and only after other possible steps have been exhausted: outdoor classes in the shade, extended recesses, fans, drawn shades and the postpoement of important testing. Cool heads, if not much else, had best prevail.