The day I decided that TV is not completely the instrument of evil that some experts would have us believe was the day my 2-year-old pointed to a stop sign and, to my shock, yelled: "Octagon!"

When Cade soon after pointed out a trapezoid ("trap-doid!") in a book and could easily tell ovals from circles, I started pointing to objects all around the house. He not only got all his squares and triangles, but even managed a "cwescent" (crescent) and "hot" (heart) in his lispy little baby voice.

My first impulse was to shout from the rooftops that I had the most brilliant child in history, especially since my husband and I at the time hadn't yet tried to teach him these shapes. But the baby couldn't have just spontaneously come up with the answers; there had to be something else at work.

Turns out, it was someone: Blue and Joe, to be exact.

I'm embarrassed yet grateful to say that all the time we were parking Cade in front of "Blue's Clues" for bedtime milk, thinking it was just buying us time for kitchen chores, he was learning beginning geometry.

This hasn't suddenly made me a cheerleader for TV. But it has convinced me that letting your children watch limited, carefully chosen educational shows — or, OK, even a cartoon with no redeeming value once in a while — can have at least a few pluses.

I didn't always feel this way. In my house I've long been the TV Meanie. I've been known to growl about the "zombie maker," or the "electronic sedative," and abruptly shut the TV off, to weepy protests. I've taped articles on TV's detrimental effects to the bathroom mirror. I've even threatened to make our home boob-tube-free.

Most of the hazards of TV- watching, you already know: the suspected links with behavior problems, obesity and other ills. Even family shopping trips have been complicated by TV — on top of being the cause of my daughter's whining for princess toys, it is the reason my son likes to copy a certain cartoon zebra and spit his juice onto the cart.

So I'm still wary of the television. I remain intensely mindful of the American Academy of Pediatrics' recommendation for kids like mine: Keep screen time to no more than one or two hours a day. We try to watch together and discuss. I try to minimize the kids' tube time and maximize story and play times.

Even so, my disdain for the flat screen has evolved into a sort of grudging love-hate, because I've seen the small bits of good it can do.

"Sesame Street" and educational shows like it have built on our efforts to teach the kids not only shapes and letters, but a love for science and music and culture. Many shows also stress the people skills kids need to get along in the world — solving problems, cooperating, sharing your cookies. This is welcome reinforcement, because one funny thing about human nature is that lessons sometimes stick best when they're heard not just from Mom and Dad, but someone else, like, say, a Muppet.

The kids' repeating movie dialogue ad nauseam can be annoying. But as they keep surprising me with their ability to recall and discuss long stretches of plot, I like to imagine (or at least convince myself) that it's helping them develop story-sequencing and comprehension skills that will come in handy as they learn to read. (And OK, I admit it: Few things amuse me more than the kids' rendition of the "You! Higher mammal! Can you read!?" scene from "Madagascar," complete with the sound of Rico the penguin gagging up a paper clip.)

We've even been able to scrounge a few teachable moments from TV's poor examples. When one "Madagascar" penguin slaps another, I ask my kids how the second penguin feels. Now when any TV character is mean, my son says, "That's not nice," then my daughter says of the victim, "She's sad." (Then Mom thinks, now if only my kids would remember these points and quit whacking each other.)

Finally, surrendering the children to the tube now and then gives my husband and me a few minutes of couple time to chat and reconnect after a hectic day apart, even if the moment is only as romantic as its "Barney" background music.

So I guess I'll have to take TV's bad with the good. Besides, since Barney's singing, "With a great big hug and a kiss from me to you," sends our tots running to us every time for hugs, it can't be all evil, right? During one of these snuggles, my son pointed to the logo on my shirt and said, "Oval," and I had my answer.