HAVE RECENTLY discovered my 92-year-old grandfather. Almost, but not quite as if he were an unknown continent, situated beyond the equator of my known family geography. This is not to say that I was not acquainted with him or did not ever see him or did not send an annual Christmas gift (handkerchiefs. usually) from him. It was simply that he, living in another city, had no real presence as far as I was concerned.

But now I have made contact with him, heard him -- really heard him -- for the first time. Now, before it became too late, I have leaned close in order to catch his frail voice telling me of the hired girl in Cotton Plant, Arkansas, fo his general store in the Missouri lead belt, of life when the world was different. And like any explorer who claims a new shore, I'm ruefully certain of one thing: it was always there.

Various publishing programs for young people have begun to recognize the need to provide books which integrate older men and women with the rest of the world, to remove them from the realm of rocking chairs and hearing trumpets and dutiful longdistance phone calls, to make them as alive to readers as my grandfather has become to me.

Several recent titles can be recommended for their success in closing this largest of generational gaps. One, George Ancona's Growing Older , is an oral history of a diverse group of elderly people which deserves readers of all ages. Its well-designed format uses photographs and text to show the vitality, in mind if not always in body, of 13 men and women: among them, Millia Davenport, a lifelong cosmopolitan now in her midlong cosmopolitan now in her mid-80s; Richard May, at 95 still working in his New York office; Henry Wilson, a 100-year-old descendant of freed siaves.

Much in this book will have a comforting yet disturbing familiarity to anyone who has meditated on mortality. Its value cannot be strictly defined; hearing people speak straightforwardly with pride and humor about their own old age -- the triumphs, frustrations, memories and uncertain futures -- can only have a ripple effect, with their phrases and thoughts recurrin within the changing texture of our own lives.

Kidnapping Mr. Tubbs , a novel by Don Schellie, stays with us in another way -- leaving us smiling at the ornery eccentricity of humankind, young and old alike. Once a cowboy, "homely old man Tubbs" is a victim of geriatric-care good intentions -- not "sick, just old," he's confined to an Arizona nursing home until he decides to "go back up north for one more look at things" before he dies. Garrulous though "deef," and determined, he coerces two teenagers into taking him on a final, nostalgic trip upstate to the ranch where he spent his best years. So, crammed into a Volkswagen, with Mr. Tubbs' beloved saddle taking up a lot of the available space, A. J. Zander and Eloise Ann Spencer and the elderly cowboy set out on his sentimental journey, only to find, after a harrowing all-night trip, that Happy Hacienda Ranch Estates have usurped the wide, open spaces where once he did roam.

Not surprisingly, considering the ambiance, this is a story which contains a lot of horse sense. Mr. Tubbs is a perverse old coot and walking example of "local color"; he's also a man whose friendship becomes important to a 16-year-old boy who had previously decided that old people made him feel "peculiar." Schellie has created a trio of characters whose adventures are beguiling and warm-spirited.

Reubella Foster (named for her two granddparents, Reuben and Ella, and not after the virus) doesn't have any problem reiating to older people; it's the middle generation, represented by her rather unstable father, that troubles her. And when we first meet her, in Suzanne Newton's novel, Reubella and the Old Focus Home , she's running away.

But she doesn't get very far -- on the outskirts of the small North Carolina town where her dad owns a mostly unvisited tourist home, she is stopped by three bizarrely clad elderly women traveling in an aquamarine van. Learning that they need a place to stay, she suggests the Foster Lodge and then reluctantly agrees to accompany them back there, postponing her flight until the following morning. However, one thing leads to another, and before Reubella knows what is happening, she and her father have been transformed into the proprietors of an "old Focus Home," which is intended to be for "nurturing" and not nursing. Hollis Nesselrode, Constance Crom well, and Ernestine Smithers are nearing the last plateau of their lives, and they think the Foster's immense yellow house looks like the place to spend it. Unwilling to turn into fourth-class citizens, the three women, accustomed to independence, want to use their energies to create a world with a shape to accomodate them, and they involve Reubella and her father and the community in the effort.

Setbacks do occur, but even the realization that their bodies eventually will betray their minds, does not stop the Old Focus Home from becoming like "the traditional French pot-au-feu, simmering forever with new ingredients added each day."