DEAR ABBY: I feel compelled to respond to Veronica M. DeCrescio's letter about how she always wanted to be a teacher, but never went back to school to certify.

Please tell her to GO FOR IT! I am in a similar situation. I earned a B.A. in an unrelated field, but later realized I wanted to become an elementary school teacher. I am going after it -- even though it means I will be a student teacher at 50.

I am in school now and have five more quarters to go. This time around, college is even more intellectually stimulating and satisfying than before. Most of the students in my program are under 30, and I am old enough to be "Mom" to several of them. Age can be an advantage -- I have had life experiences these youngsters have yet to learn. Moreover, I have had the time to think about taking this life-changing step and am fully committed to my dream of becoming a teacher.

If I can do it, anyone can. We all have something of value to contribute to the field of education. Please assure Ms. DeCrescio that devotion and enthusiasm for the profession of teaching are much more important than one's age! -- MS. RANDALL START, BREMERTON, WASH.

DEAR RANDALL: True. I'm pleased to see someone with your life experience going into elementary education. People who love what they do are usually very good at it. You'll be a terrific role model for your students to emulate. Read on:

DEAR ABBY: Your response to the individual who got her degree but was not certified to teach school was incomplete. If you meant she should try teaching and see if she likes it, I agree. But she should realize that substitute teaching without proper certification will get her nowhere unless she's willing to work in a private school for low pay, or work in a position where there are no health or retirement benefits.

This wanna-be teacher could, however, check with her local schools and see if they help uncertified staff go back to school. In my district, many of our teaching assistants have obtained certification in this manner and are now working as full-fledged teachers.

She also needs to check the local colleges and find out exactly what is needed to earn her certificate. It might come as a pleasant surprise, since she already has a bachelor's degree.

Please wish her good luck from me, Abby. You were right when you emphasized the need for good teachers. -- VETERAN SCHOOL SECRETARY, SYRACUSE, N.Y.

DEAR SCHOOL SECRETARY: Let it be lost on no one that one of the most important jobs in this country is teaching. Teachers can influence and motivate an entire generation.

DEAR ABBY: I am a college freshman, extremely shy, and not the most popular guy on campus. There is a girl I like, but she hangs out with a far more popular crowd. I talk to her often -- in school, online and on the phone. I would like to ask her out, but I am afraid she'll say no. What should I do? -- HOPELESS FOREVER IN NEW YORK

DEAR HOPELESS FOREVER: Ask her out for coffee. It's nonthreatening and it's not a formal date. It's two friends chatting and getting to know each other. Then ask her to a movie. If she's spending time talking to you on the phone and online, she's interested in you, too. Take a deep breath, count to three -- and call her now!

For an excellent guide to becoming a better conversationalist and a more attractive person, order "How to Be Popular." Send a business-size, self-addressed envelope, plus check or money order for $5 (U.S. funds only) to: Dear Abby Popularity Booklet, P.O. Box 447, Mount Morris, IL 61054-0447. (Postage is included.)

DEAR ABBY: I have a brother, "Stan," who has been homeless for a decade. Stan is borderline schizophrenic. He goes through periods when he hears voices, believes things to be true that aren't, and does not keep himself clean. He has always had trouble dealing with people.

Although I am younger than Stan, I have taken on the responsibility of sending him money, getting him out of trouble, etc. He is often unappreciative, but I realize his problems are beyond his control.

Every day I thank my lucky stars that I am mentally healthy and can get up every morning with the resolve to work and enjoy my life and relationships with people.

I'm writing because I often hear others make comments about "the homeless" -- that they are lazy, drunk, etc. People don't realize that while they're airing their distorted views, a relative of a homeless person could be in their presence.

I have struggled with Stan's mental illness and the problems it causes him, trying to get him proper treatment and shelter. For people to imply that I should tell him to get a job conveys nothing but ignorance. Homeless people have a disability that is not visible.

So why do people persist in believing the homeless choose their fate? Because it means they don't have to feel compassion or try to help. Please print this so people will open their minds before making insensitive, ignorant, black-and-white statements. -- SISTER WHO CARES IN NEW JERSEY

DEAR SISTER: I'm not sure that I agree with your conclusion that people persist in believing the homeless choose their fate so they won't have to feel compassion or try to help.

I think there is an element of fear when we are confronted by the homeless. Some of them are so ill, talking to people who aren't there, that there is a fear they might become violent.

Also, many people live from paycheck to paycheck. In other words, they're only a paycheck away from being homeless themselves. And that in itself is so frightening that people want to distance themselves so they won't have to think about that terrifying reality.

DEAR ABBY: I have been friendly with "Janet," my neighbor, for 12 years. When my daughter "Heather" turned 19, she moved out. Heather, who is irresponsible and immature, then went behind my back and asked Janet to co-sign for an apartment for her and one of her girlfriends. Without consulting me, Janet agreed.

Well, Heather and her friend got evicted, owing their landlord $2,400. Janet called me and told me I should pay her for Heather's portion of the rent. I told her, "Sorry, I can't help you." Janet became very upset and now refuses to have anything to do with me.

Heather enlisted in the Army and is out of the country. Janet still calls and threatens me. I feel bad about this because she was a good friend. What do I do? -- A MOTHER IN FRESNO, CALIF.

DEAR MOTHER: Do nothing. Janet made a bad business decision that has nothing to do with you. Also, Janet is NOT your friend. She conspired with your child to undermine your authority as a parent. She has learned an expensive lesson the hard way. Now please stop grieving for her.

To order "How to Write Letters for All Occasions," send a business-sized, self-addressed envelope, plus check or money order for $5 (U.S. funds) to: Dear Abby -- Letter Booklet, P.O. Box 447, Mount Morris, IL 61054-0447. (Postage is included in the price.)

DEAR ABBY: I work in the office of a trucking company. One of my four co-workers is a married man. I'll call him Tom. The rest of us are females. A divorced female truck driver comes into the office and can't keep her hands off Tom.

Every chance she gets, she rubs his neck, shoulders or back while he sits there looking embarrassed. She also tells him dirty jokes. The other women and I think her behavior is inappropriate.

When Tom's wife found out about this gal, she told him to put a stop to it because it shows a lack of respect for their marriage. He has asked me and the other women more than once how to handle this problem. I told him I'd write you, since we read you every morning on our breaks.

What do you say, Abby? We're awaiting your advice. -- THE OFFICE GANG

DEAR OFFICE GANG: Tom is a big boy. He ought to be able to discourage the woman's advance without our help. However, if he lacks the courage to speak up, he should discuss the matter with the office manager. It's his or her job to intervene if one of the employees is being harassed.

DEAR ABBY: My dad and I are partners in a home-based business. He has repeatedly told me he wants our business to be successful. However, when it's time to put his nose to the grindstone, he makes up one excuse after another and leaves it to me.

I love my dad. However, I have wasted a lot of time and money trying to get him to fulfill his responsibilities. Should I give up and work the business on my own? -- DISENCHANTED DAUGHTER IN CANADA

DEAR DISENCHANTED: Perhaps your father is finding the business stressful and would like to be bought out. Have a heart-to-heart talk with him and ask him if that's the case.

P.S. It is important that you talk to a lawyer about this "partnership" before you invest more time and money in the business.

DEAR ABBY: The letter in your column about a father explaining "the birds and the bees" to his 7-year-old son brought back the memory of my experience with my 6-year-old son.

I sat him in front of the television to watch a program on human reproduction. After the show, he told me that he understood everything except how the male seed got to the female egg. I said he was too young to know, and I would tell him when he was a teen-ager. He threw up his hands and said by that time, he would have forgotten the question.

After some pleading and a solemn promise not to tell his mother where he'd gotten his information, I told him. He stared at the wall for about 20 seconds, turned, looked me straight in the eye, and said, "Dad, that's the most disgusting thing I've ever heard." -- R.W., RAYMOND, N.H.

DEAR R.W.: I'm sure his opinion changed once his testosterone kicked in. Read on for a story that approaches the subject from a different angle:

DEAR ABBY: The letters about children learning the facts of life reminded me of this old story:

A country doctor went to deliver a baby. The expectant mother's 5-year-old son was with her and the delivery was imminent.

The house had no electricity, so the doctor brought out his lantern. He instructed the little fellow to hold the lantern while he delivered the baby. After the baby was born, the doctor spanked it and it began to cry.

Turning to the little boy, the doctor asked, "Well, son, what do you think of your baby brother?" "Hit him again," the boy replied. "He ought not to have climbed up there in the first place." -- ROWENA IN KANSAS CITY, KAN.

To receive a collection of Abby's most memorable -- and most frequently requested -- poems and essays, send a business-sized, self-addressed envelope, plus check or money order for $5 (U.S. funds) to: Dear Abby -- Keepers Booklet, P.O. Box 447, Mount Morris, IL 61054-0447. (Postage is included in the price.)