Dear Abby: I would like you to know what a positive impact your advice has had on my life. In May 1989, at the age of 471/2, I was laid off from my job at the local telephone company in Ketchum, Idaho. In addition, my husband had just been transferred to Twin Falls. At an age when most of our friends were settling down as empty-nesters, we were in a state of flux with a major move and a new career for me.

I had no computer skills for today's job market and no desire to work in retail sales. While discussing the possibilities with our daughter, who was away at college, she asked me what I'd do if I could do anything I wanted to do. I said, "I'd teach mathematics." I had always loved math and knew that there was (and is) a serious shortage of math teachers. She said, "Go for it, Mom!""No, it's too late," I responded. "I'd be at least 52 years old before I'd be back in the work force." Then I remembered something I read in your column: Never put off starting something because of how old you will be when you finish. So in June 1989, terrified of failure, I enrolled in junior college in Twin Falls, Idaho.

To make a long story short, on May 1, 1994, I graduated from Boise State University with a bachelor of science degree - magna cum laude! It turns out that I like teaching more than I ever thought possible. My life is filled with new friends, new challenges and, most important - joy.

I am grateful to my family for their support, especially my daughter for encouraging me to go back to college - and to you, Abby, for pointing out that I would have been 52 this year, whether I went back to school or not.

- Nancy J. Robinson,

Twin Falls, Idaho

Dear Nancy: Congratulations! And on the chance that you didn't save the letter that changed the course of your life - here it is:

Dear Abby: I am a 36-year-old college dropout whose lifelong ambition was to be a physician. I have a very good job selling pharmaceutical supplies, but my heart is still in the practice of medicine. I do volunteer work at the local hospital on my time off, and people tell me I would have been a wonderful doctor.

If I go back to college and get my degree, then go to medical school, do my internship, and finally get into the practice of medicine - it will take me seven years. But Abby, in seven years, I will be 43 years old! What do you think?

- Unfulfilled in Philly

Dear Unfulfilled: And how old will you be in seven years if you don't go back to college?

Dear Abby: Regarding whether fathers should tell their daughters dirty jokes: I say no, which brings to mind this story:

A constituent of Gen. Ulysses S. Grant asked if he wanted to hear a dirty joke, prefacing his question with, "I see there are no ladies present."

Grant replied, "Yes, but there are gentlemen present."

I rest my case.

- A Gentleman in Madison

Heights, Mich.

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