Have you ever sniffed an apple pie--and remembered learning how to bake at your grandmother's house? Have you ever caught a whiff of an old baseball glove--and remembered playing catch out in the back yard with your grandfather? Does your shampoo bring back faint memories of your great-grandparents' home, which you only visited when you were a tiny toddler?

Just about everybody has experienced moments when smells, or scents, awaken memories. And scientists have proved that scent and memory are closely linked in the human brain. That's because smells are processed in the same part of the brain that deals with memory. Under certain circumstances, the brain stores memories and smells at the same time. Later, when smell molecules that you sniff into your nose stimulate the brain, it retrieves the smell--and the memory that's connected with it.

Take that apple pie, for example. Let's say that one day long ago you smelled pie baking--and you felt strongly connected to your grandma. She was teaching you how to make crust and mix up spices, apples and sugar for pie.

Your brain was busy that day. It was processing the smell molecules from the baking pie. It was recording the new experience of baking so you'd be able to do it again next time. It was also registering the wonderful feeling of being with your grandmother--and it was doing all those things at the same time. Ever since then, when you suddenly smell that cinnamon scent, your grandmother's beloved face has popped into your brain. And the great thing is, pie will go on calling up those happy memories for years and years to come--all the way into your own old age.

Of course, you can also capture happy memories with glue, scissors and paper. Two new books, just published by Kids Can Press, encourage grandchildren and grandparents to create memory scrapbooks together.

The $4.95 paperbacks, by Jane Drake and Ann Love, are called "My Grandfather and Me" and "My Grandmother and Me." They're designed for kids aged 5 and up. Each book contains space for a member of each generation to write down facts and memories. If you can't think of what to write about, some pages have check boxes to get conversation going. For example, a few of the boxes prompt answers about where kids and grandparents live. Something as simple as that can spark conversation about the difference between your home and the farm where your grandfather grew up, or the similarities between the "old country" your grandmother emigrated from and the place where you live now.

There's also space to paste in photos and to draw pictures. In the back of each book is a pocket to tuck letters and souvenirs into.

Other subjects the books encourage kids and grandparents to explore include:

* Favorite holidays to celebrate together.

* Special places to visit together.

* Ways they are similar and ways they are different.

If your grandparents live far away, you might think about making a scrapbook through the year that you can give to them as a holiday gift. You could do one page for each month, and put in a picture of something great that happened then, or paste in a cartoon you thought was funny, or tape in a photocopy of a great report card you received. The idea is to create a record of you--kind of the story of your life! Your grandparents will like reading that MUCH more than they would enjoy a store-bought greeting card.

If you're lucky enough to have older relatives close by, making a scrapbook is a way to spend time together. It's may feel like an old-fashioned way to pass the time, but the scrapbooks that result will last a lifetime. When you're grown up, taking a peek at one of the books will bring back memories of happy times you spent with some of your favorite people.

Tips for Parents (and Grandparents)

Perhaps as an antidote to this high-tech age, how-to publications about making memory books are proliferating. "Classic Scrapbooking: The Art & Craft of Creating a Book of Memories" (Hartley & Marks; $19.95) provides ideas for themed memory scrapbooks and explores bookbinding, papermaking, flower pressing and more. Another title, "Making Memory Books" by Amanda Lewis (Kids Can Press; $5.95), is written especially for kids aged 8 to12. Both encourage you to spend the long fall evenings going through those cluttered boxes of family photos and mementos to create keepsakes for your family.

For You to Do

Want to exercise your memory? Here's an experiment to try. Ask a friend or family member to tie a blindfold over his or her eyes. Make sure not to tie it too tight. Then let them sniff five different smells that you have prepared in an "odor kit."(Make them nice smells. After all, this is supposed to be fun!) You could try vanilla, soap, a branch of fresh pine, baby shampoo, some perfume and so on. Ask the subject of your experiment to say the very first thing that each smell calls to mind. Then trade places and try identifying some smells that your friend or family member has picked out.