"It's the greatest investment you can make," I said, over and over. But a call last week from a woman named Maria made it clearer than ever that dollars -- and the absence of them -- are warping the way parents think about college for their children.

In Maria's case, she's so broke that she says she may choose not to pay for her child to go to college. She sketched her situation in a weary tone that told me she had done the sketching before:

Single mother. Is an executive secretary for an Alexandria trade association. Lives in a $600-a-month first-floor apartment in western Fairfax County. Has a 16-year-old daughter who goes to public school. Carries about $5,000 in nagging credit card debt. Gets no regular help from her former husband or anyone else. Has no savings or family from which to borrow. Earns about $35,000 a year.

Maria wants her daughter to go to college "so she does better than I have -- isn't that what every parent wants?" Her child shows great potential, according to Maria. The daughter's grades are excellent and her study habits are diligent.

"My daughter has already been told that she could go to the University of Virginia, Virginia Tech, maybe even a school out of state someplace," she said. But none of it will happen without a massive loan, according to Maria. She is very wary of taking on such a burden.

"I paid cash for my car, and I pay cash for all my clothes," she told me. "The reason I have the credit card debts is that I had to go home to Colorado for a funeral -- my uncle -- and my daughter and I had to fly. That was about $1,200. Then I had car trouble, and I had to pay my lawyer from when I was getting a divorce. It added up. You know how it goes."

Indeed, I do. But I don't understand why a person would take on debt for needed car repairs and needed trips to funerals, but not for needed education -- and I told Maria so.

I also pointed out what very few parents of any income level bear in mind. It isn't just parents who can take on loans to finance college. Students can, too.

Not only that, but students can work part time (or even full time) to pay the school tab. In addition, there are many obscure scholarships at every school, for which Maria's daughter might be eligible. Meanwhile, good old Uncle Sam still lends money at low interest rates under some circumstances.

And where is it written that a four-year school is the only option?

Two-year community colleges do an excellent job of preparing students, at vastly cheaper rates. Best of all, those two years count toward a four-year degree in many cases, if a student transfers to a four-year public college in the same state.

Education is indeed indispensable, I told Maria. So is knowing all your options.

From deep in the bowels of the federal government, an anonymous question about etiquette.

My correspondent works for an agency where most of the doors do not have windows. They are steel, they are black and they are impossible to see through.

When you come to a pair of these doors, my correspondent says, it used to be understood that you'd keep right, as if you were driving. You'd live longer that way.

But lately, "it is increasingly common for people to come busting through the left side door." Some people have been "nearly leveled," my correspondent says. Others have "stopped dead in their tracks with shaking coffee cups," having barely avoided a head-on collision.

My correspondent always makes it a point to apologize after a near-smash, even if the other guy is on the wrong side of the road. But the oncoming sinners "just glare at you and don't say anything," my correspondent reports. He/she wonders what I make of all this.

First and foremost, my friend, we need an emergency appropriations bill introduced on Capitol Hill to provide doors with windows at your agency. But knowing how long that might take . . .

How about handwritten signs on each side of the doors that ask people to keep right except to pass? The signs wouldn't need to be threatening, confrontational, nasty or ugly. They could even be pretty (if someone's kids got busy with crayons or watercolors). I wouldn't mind a bit of whimsy -- something like "Keep right, please, or my coffee might end up redecorating your shirt."

But I suspect the best answer might be something very direct -- such as, "Unless you keep right, this heavy steel door may fly open and smack you in the head, and that might ruin your whole day."

I could claim that a large black door hit me in the head and caused my fingers to err. In fact, there was no door -- just a couple of careless mistakes, both involving misspelled names.

In a column a few days ago, I wrote about an angel of a woman who returned three lost wallets, contents intact. Her name is Pawin A. Sultan.

Then, in a column last week, I referred to a restaurant consultant as Linda Ross. Close but no cheroot. She's Linda Roth. Major sorries to both.