Letters from readers make my day. That has been true for more than 45 years, since I wrote the first of my juvenile books. The finest encouragement a writer can receive comes in the form of letters from his (her) readers.

Juvenile readers are the finest teachers of all. I really am convinced that the human mind constantly is improved through the disorderly, rowdy, never-ending banter of child to child from generation to generation. Kids have taught me more about the world, about myself, and about writing than any formal education I ever had.

Josh was a bright nine-year-old who wrote me from Michigan every week. Then he began calling me long distance a couple of times a week, frequently at around midnight.

My wife would groan, mumble "Josh again," and roll over. During the fifth phone conversation I asked Josh if his parents knew he was calling me. He replied, before going on to matters of greater significance, "My parents are very rich, so that isn't important." So maybe money isn't so important, I said to myself. Josh and I corresponded for years. Enclosed in his final letter was a snapshot of Josh dressed as Elton John in his glory years.

Many years ago Travis wrote me a somewhat desperate letter with strange priorities. 'I am writing a book, and first of all I need some names. I don't mean something like Tom or Dick or Alice. I need something hot like the Pest, or Shoie, or Alvin. I also need a good publisher, and I need an artist. Thanks for your help, Travis Prescott. P.S. Could you also send me some tips on writing?"

Kids--at least kids who read books--are eternally optimistic. There's always a ray of sunshine. In fact, the world is almost all sunshine. Never mind El Nino, let's talk about the wart on Uncle Rodney's nose. Christy wrote me: "Saturday we had a car accident. My sister Tracy strained and sprained her muscles, and Tammy Uline has a broken collarbone, her jaw broken, 35 stitches and a fractured skull. There's something wrong with my collarbone. My dad wasn't hurt. Our car was totaled, so he says we'll probably get a new one. If so, he says it probably will be a Pontiac Lemon. What great news!" That letter brightened my day. A week later, a second letter came from this same eternally optimistic girl. This time she was ecstatic: 'I have a brace for my collarbone. I have to wear it 10 weeks. A nice thing is that I don't have to take any phys ed during that time. Also, Dad promised us three wounded girls he'd buy us each a banana split. Accidents sure have lots of advantages!"

Nine-year-old Gordon's letter sent me to a real high. He suggested that I team up with Beverly Cleary to write a book. The reader, he explained, could experience the antics of Alvin, Shoie, the Pest, Henry Huggins, Beezus, Ramona and Ribsy, all within the same covers. What great company Gordon put me in!

Good readers tend to be fine writers themselves. When Colleen was 10 years old she wrote me: "When I lived in Maryland there was a huge library nearby, and I spent at least four hours a week there--more often up to nine hours. I love to wander around in a library; sometimes I just sit and smell the fragrance of books around me. More often I pop as many as 15 books into my bulging bag. Once I staggered out the door and then dropped the whole bundle all over the icy steps. I knelt there and cried until a little old man wearing a white beard and a smile helped me pick them up." What an evocative passage, written by a 10-year-old! My friendship with Colleen has grown through the years. She and her own children visit us periodically, hiking our forest trails and tossing pebbles into our stream.

Sometimes kids write pure literature. Here is one of my favorites, in its entirety. 'Dear Clifford: It's me, Kevin Miller." In my opinion that's more succinct than "Call me Ishmael."

Some years ago my youngest son Gary, a true Fernald fan, placed Alvin's name on the internet. Since then I have been enjoying one of the greatest thrills of my 85 years of life: Almost daily I have been receiving e-mail fan letters from adults who read my books 40 or more years ago. What joy! Here are just a few of their comments:

"Alvin's Secret Code was the book that hooked me into reading the whole series. My father and I made code wheels and scytales sitting at the dining table. We also practiced inventing and solving ciphers--one of my favorite memories."

"Your books had such a fundamental influence on my current makeup that it is rather like trying to put into words what my DNA means to me."

"Recently my brother and I (ages 33 and 31) bought some Alvin Fernald books at a used book sale. We loved those books in grade school, some 20 years ago, and reading them, were inspired to dig out the copies of the titles we already owned. Craving still more, we even went to the local elementary school and checked out the remaining Alvin titles. In short, for the past two weeks we have been on an Alvin Fernald binge, rereading some of our favorite books of all times, and finding that, unlike many things from grade school, they hold up as well as ever."

"I'm 34 years old and I have an eight-year-old daughter. We are just about to finish reading The Marvelous Inventions of Alvin Fernald. I kept my hardback copy for over 30 years just to share this wonderful story with my kids."

"When I grew up in Ossining, NY, I read your books constantly. I spent countless nights waiting for my parents to go downstairs so that I could open my bedroom door wide enough to read Alvin books by the light from the hallway. From seven years old onwards I haunted the library's book sales each year, buying worn Alvin Fernald discards for 25 carefully saved pennies apiece."

"I was addicted to the boy genius books: Encyclopedia Brown, The Great Brain, The Mad Scientists Club, Danny Dunn and any others I could find. But Alvin Fernald was, and remains, the standard to which everything else was compared."

"I became a superhero after reading Alvin Fernald, Superweasel. I used to skulk around the park across the street from us, cleaning up litter and dumping it in the trash, then putting my hands in my pockets and casually sauntering home to my civilian identity."

"I am a 31-year-old fourth year medical student. When I was a child I read The Marvelous Inventions of Alvin Fernald. It was without a doubt my all-time favorite book. You'll never know what it meant to me."

"Alvin inspired me to do and try things I would not have tried."

"The bottom line is that I want to say thank you for writing those wonderful adventures; they gave me weird ideas, fun daydreams, big laughs and tons of pleasure."

Pretty heady stuff for any writer to receive!

Whenever I find myself enjoying this euphoria perhaps a little too much, I force myself to go back to a certain file of letters from the kids themselves. Kids, for the most part, are totally honest, which is the same thing as saying they can be brutally frank. Ten-year-old Todd kicked me in the shins a good many years ago: "Your book was the most exciting book I've ever read. It was also suspenseful. I couldn't put it down. Sometime I hope to finish it."

And consider this one, a knife in the ribs, from a lad in Jamaica, NY: "I just finished reading your book called Alvin's Swap Shop. It was very funny. But I didn't get the meaning out of the story. Please send me an explanation. The best part was in the middle. What happened at the end?"

And, finally, how's this for honesty? "Every time I go to the library I ask the lady if there are any book that hasn't been tooken out yet. And she said, no one ever touch your book, and so I got it, and the people are missing out on all the fun."

I am proud, and inexpressively humbled, to receive letters such as those detailed here. My Alvin Fernald books have been out of print for years. Two will be republished by The Purple Press and Bethlehem Books in 2006. Hopefully, others will follow. Perhaps another generation will not "miss out on the fun."

But any fun my readers may have experienced cannot possibly match my own fun, yes my supreme satisfaction, in seeing my books reborn for the kids of "my kids."