DEAR ABBY: At 4 years old, my son John is getting to the age where he's occasionally invited to the homes of his schoolmates.

Last week, a parent I'll call "Mr. Smith" invited John to spend the afternoon at his home playing with his son. John had a great time, but when I picked him up, he described deer heads on the wall -- and to my horror, the guns in the house!

Obviously, Mr. Smith is a hunter and there's no doubt that the guns John described were real.

I have decided not to let John go back, but I feel awkward bringing this up with the Smiths. I don't want to appear rude, since both parents are very much involved with the preschool our children attend.

Abby, I don't ever want my children in a home with guns, but how should I handle this without offending the parents? -- CONCERNED MOM

DEAR CONCERNED: Your child's welfare must come first. Be up-front about it when an invitation is again extended. Tell the Smiths that your son mentioned the guns in their home, and you prefer that when the children play together, they do it in your home under your supervision.

DEAR ABBY: I am amazed at the number of credit card receipts drivers leave behind after using their bank cards at gas pumps. This is very risky business because the account number is on the receipt.

Abby, please warn your readers either to take their receipts with them, or to press the "no" button when the computer asks if they want a receipt so that it won't print one. -- CAREFUL ABOUT MY CARDS

DEAR CAREFUL: Thanks for the warning. People should also take their receipts with them after using ATMs (Automated Teller Machines), and destroy them before disposing of them.

DEAR ABBY: I am amazed at the number of credit card receipts drivers leave behind after using their bank cards at gas pumps. This is very risky business because the account number is on the receipt.

Abby, please warn your readers either to take their receipts with them, or to press the "no" button when the computer asks if they want a receipt so that it won't print one. -- CAREFUL ABOUT MY CARDS

DEAR CAREFUL: Thanks for the warning. People should also take their receipts with them after using ATMs (Automated Teller Machines), and destroy them before disposing of them.

Good advice for everyone -- teens to seniors -- is in "The Anger in All of Us and How to Deal With It." To order, send a business-sized, self-addressed envelope, plus check or money order for $3.95 ($4.50 in Canada) to: Dear Abby, Anger Booklet, P.O. Box 447, Mount Morris, Ill. 61054-0447. (Postage is included.)

DEAR ABBY: "Dorothy in Long Beach, Calif." asked you to stop referring to repetition as a "broken record," and added, "You'll never hear anything from a broken record because it is broken." She said, "Please say well-worn or scratchy instead," and asked you to sign her letter, "A Retired Public School Music Teacher."

You thanked her for writing and said you'd try to change your tune. Abby, I'm a collector of old phonograph records, and I wonder if either one of you knows the origin of "a broken record."

It goes back to the days before tapes and CDs replaced old-fashioned phonograph records, which were made of shellac or plastic and easily broken or damaged. Those records rotated at 78, 45 or 33 1/3 revolutions per minute. Some, especially the hard shellac ones, would crack or break -- sometimes on only one side of the surface.

When the needle hit the damaged spot, it would jump backward into a preceding groove, and replay until it hit the same spot again and jumped backward again, etc. In other words, it caused pure monotonous repetition of the same words and music.

A well-worn or scratchy record does not connote the same thing a broken record does. -- ROLAND GUERIN, HARVEY, LA.

DEAR ROLAND: Thanks for your supportive letter. Now I'm sorry I didn't respond to "Retired Music Teacher," "You're mistaken, you're mistaken, you're mistaken."

You're not the only reader who commented on that letter. Others also want to go on record:

DEAR ABBY: The somewhat caustic note from "Dorothy in Long Beach, Calif.," regarding a "broken record," speaks more of her intolerance and rigid thinking than of the facts.

As you know, a broken record in our generation meant that a groove in the record was "broken," and each revolution caused a duplicate sound over and over (so go ahead and use that idiom if you please).

I frequently use figures of speech from my past that cause my children's and grandchildren's eyes to glaze over as they wonder what in the world I mean; e.g. "Cheese it -- the cops!" or "You're not just whistlin' Dixie."

They do not need to adopt them, but neither do they have a right to chastise me for doing so. -- ROBERT E. SMITH, LITTLETON, COLO.

DEAR ABBY: This is in response to Kiki's mom, who gave her 2-year-old daughter the car keys, which the child promptly inserted into an electric socket.

The mother admonished herself for being "stupid" for having given her daughter the keys, but not for leaving the sockets exposed!

All electrical outlets should be covered with outlet protectors.

This was your chance to educate people as to the danger of leaving electrical outlets exposed. You blew it, Abby. -- ANN FOSS, EDEN PRAIRIE, MINN.

DEAR ANN: You're right. Parents of small children should visit their local hardware store to learn the options available for childproofing the electrical outlets in their home.

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 $3.95 ($4.50 in Canada) to: Dear Abby's "Keepers," P.O. Box 447, Mount Morris, Ill. 61054-0447. (Postage is included.)

DEAR ABBY: I can relate to "Elizabeth B. in Fresno, Calif.," who is struggling on welfare and has to contend with the disapproval of others. When I was 19, my husband walked out on me and our infant. I had nowhere else to turn, and was on welfare from 1975 to 1978.

Abby, after I received my AFDC check and paid my rent, phone and light bills, I had $5 left each month. Food stamps cannot be used to purchase diapers, toiletries or even laundry detergent. If it hadn't been for my family sharing these items with me, I don't know what would have happened to us. Because I was so embarrassed by the disparaging looks I received, I tried to shop for groceries when the store was least busy.

Things began to turn around when my case worker phoned to tell me about a job that was available through the CETA (Comprehensive Employment Training Act) program. My first job was clerking for the Department of Public Assistance. While I was learning skills, I was earning an income, and I have been working ever since.

Hang in there, Elizabeth, and don't give up. I know it's hard to ignore the nasty remarks and looks, but someone will give you your chance. I have owned my own business for eight years now, and I would hire you. -- WORKED OFF WELFARE

DEAR WORKED OFF WELFARE: I'm printing your success story for Elizabeth and others like her to see. You are a voice for people everywhere who have struggled through difficult periods and pulled through -- not only intact, but improved. My hat's off to you.

For readers who are interested, the Job Training Partnership Act (JTPA) replaced CETA in 1983. Its purpose is to assist youths and unskilled adults enter the labor force. For more information, contact your state employment office.

DEAR ABBY: Every member of my family has two children. My husband and I have one child.

At birthday time, we invite 20 cousins to a party, yet only 10 gifts are received -- and they are not doubly expensive either.

Abby, I think each child should give a gift, not just one gift from each family. After all, throughout the year, we give 20 gifts and host 20 children at our child's birthday party.

Fair play would dictate that each child bring a gift -- or at least make the "family" gift slightly more significant.

I hate to appear petty, but after five years of this inequality, I'm angry and disappointed that my relatives haven't figured this out themselves.

Is there a tactful way for me to mention it? -- P.O.'D IN NEW YORK

DEAR P.O.'D: There is no tactful way to remind your relatives that you are spending twice as much for birthday gifts as they are. They surely are aware of it, so for you to "mention" it would be in extremely poor taste.

DEAR ABBY: Help! We named our daughter after both of her grandmothers. The first name is after her paternal grandmother and the middle name after her maternal grandmother. On her birth certificate, I spelled the middle name differently because I thought it looked better.

Now my mother says her granddaughter is not named after her because the spelling is different. I say, so what? She is named after both grandmothers. What do you say? -- NEEDS YOUR OPINION IN N.C.

DEAR NEEDS: I agree with you -- so what? Your daughter is named after both grandmothers regardless of how the name is spelled.

For an excellent guide to becoming a better conversationalist and a more attractive person, order "How to Be Popular." Send a business-sized, self-addressed envelope, plus check or money order for $3.95 ($4.50 in Canada) to: Dear Abby Popularity Booklet, P.O. Box 447, Mount Morris, Ill. 61054-0447. (Postage is included.)