Several readers have said to me recently, "Do you know which of your columns I like best? The ones in which you quote from letters that accompany checks for Children's Hospital."

Now that our campaign is over and we're waiting to see what's in the mail pipeline, I have a chance to share a few more of these letters with you:

With a check for $50 - "My father was a pediatrician, and though his involvement was with children and with a Children's Hospital 3,000 miles away, it's all the same cause, isn't it?"

With a check for $15 - "Many years ago, my daughter was at Children's Hospital. Very minor, but serious to a very young mother. About 20 years ago, my first grandson was at Children's when he was about 2 1/2 years old. It was quite serious, and he was ther for a long time. That was when I pledged to myself that I would help in every way I could."

With a check for $25 - "Did you notice as you were recovering from surgey, after it was clear you were going to live, that people seem nicer, more reasonable and more interesting than they were before your operation? I have recently had two back operations. As I was mending I noticed that Post editorials and featured writers had suddenly become almost brilliant, even though I still did not always agree with them. I did not see so many bad drivers as before. The sunsets were prettier. Haveyou noticed?" Yes, I've noticed. My wife is also prettier, and easier to get along with. She has stopped nagging, and now merely expresses repeated and sincere concern about me. It's strange how much my operation improved her.

With an out-of-town check for $5 "I really didn't want to send you any money for the hospital. It's a good place, but I figured maybe they have enough, thanks to you and Harden and Weaver. Besides, I have my own favorite charities, some closer to home. But I just can't resist sending something to show I'm glad you're back at the paper after your operation. And now that I've finally sent this check, I very much wish it could be more. I guess I really sort of wanted to send it all along."

Just to put things into perspective: I don't know how much Harden and Weaver raise each year, but I know that this column has never hit $200,000 in a single year. Yet the amount of "uncompensated" help given to needy patients last year was almost $2 million. Obviously, the hospital doesn't have too much. What we raise here is a small fraction of what's needed.

With a check for $50 - "My husband and I were penniless immigrants when we came to this country in 1962. Recently we celebrated our 50th wedding anniversary by visiting our native Germany and realized that we have so much to be thankful for. We are therefore contributing $1 each year of our good life together."

With a check for $5 - "I have had a special feeling for Children's Hospital since I was operated on there when I was 5 years old. My father was working two jobs to try to support us. I'm sure he couldn't pay the full bill, and part of it had to be forgiven."

With a check for $5 - "Repaired another plumbing leak today for my usual $5 charge." Thanks, but I think you ought to raise your fees, pal. I always tell my wife that my minimum charge for repair work is $38 for the first half hour, and she doesn't object. Unfortunately, she doesn't pay, either,but it's nice to be in that kind of wage bracket.

With a check for $5 - "The only time we visited Children's Hospital was when our youngest boy put a magnet up his nose. We know how important good medical help can be."

With a check for $64 - "On Jan, 13, your column was 31 years old and our marriage was 33 years old. The $64 is in honor of our joint anniversary."

With a check for $10 - "I lost a son 10 years ago in an automobile accident. He would have been 33 years old this month, and I send you this contribution in his memory."

With a check for $15 - "Your fund drive never really hit home until we were blessed with a daughter."

With a check for $25 - "Because we are moving into a new home, we are sending you a check for Children's Hospital. You are probably familiar with the Moslem custom of making a gift to the needy one acquires something new."

With a check for $50 - "This is given in grateful appreciation of the care and concern when our daughter was hospitalized with a rare disorder."

With a check for $25 - "Did you know that coffee cans of pennies yield just about enough to buy two more cans of coffee?"