What are the themes in the story Tuck Everlasting?
One of the driving themes of Tuck Everlasting is the idea of immortality and time, which is in every single chapter of the book. The Tuck family have been frozen in time and will never die. They are stuck at the edge of the river while the river continues to flow around them. Winnie Foster must eventually choose whether she wants to give up the natural order of life and drink from the spring, becoming immortal. But she ultimately decides that there is nothing to live for if you never run the risk of dying. It is the possibility of loss that makes life precious.
Other related themes are the idea of freedom from boundaries, and changes that happen in life. Winnie lives in a tightly-protected world where she is sheltered and overly protected. The Tucks symbolize a freedom for her, a freedom from the strict rules of her parents and a freedom from time itself. In some ways the Tucks live a loose life, traveling around from place to place, not staying anywhere too long in case someone recognizes them. However, there is some fear in their lives, too, fear of discovery and fear of what people would do with the water from the spring if they knew. Winnie is afraid of many changes that are happening or will happen in her life, but as she witnesses the Tucks trapped in their bodies, never growing older or changing, she realizes that changes are a part of life and are not a bad thing at all.
One additional theme is that of civilization vs. nature. The Foster family owns the forest, but because they're immortal they are never truly a part of it. The world of nature is subject to change, decay, and death. As the Fosters exist outside that realm they can never fully understand the significance of the forest. Fortunately, nature proves itself a good deal more effective at protecting itself than the Fosters are able to do. (Cows walk around, rather than through the forest, for example, thus avoiding the spring.) This is not a surprise; nature, because it is subject to change, can adapt to different circumstances. Of course, the immortals of the Foster family can never do this.
The source of the Fosters' immortality comes from nature itself. But the spring of eternal youth, like the Fosters themselves is in the natural world but not of it. As water, it is entirely natural, but as a magical elixir conferring immortality, it is supernatural. Like the Fosters, the immortality-water exists in a world of its own, caught between nature and civilization.
The theme? There isn't one. There are quite a few themes in the book Tuck Everlasting. It's actually kind of amazing how many themes are packed into such a short book. It's only 139 pages long, and in those 139 pages can be found themes on life, death, time, choices, love, and friendship.
The theme of love is demonstrated in a few ways. There is a budding romance between Jesse and Winnie for sure, but there are other examples of non-romantic love too. For example it's clear that the Tuck family loves each other and loves Winnie as one of their own. It's also obvious that Winnie loves the Tuck family back. It's why she is willing to help out with the escape near the end of the book.
Remember that a main plot of the book is whether or not Winnie is going to choose to drink the spring water or not. It's her choice, but it's not an easy choice, because it forces her to wrestle with very real questions about life and death.
One of the main themes of Tuck Everslasting is that death is a natural and necessary part of life. Throughout history, humans have searched and longed for a cure to death. Tales of a "fountain of youth" have been recounted for thousands of years. In Tuck Everlasting, this folklore is a reality. Though the Tuck family have indeed conquered death and become immortal, the book questions whether or not this is necessarily a good thing.
Winnie and Mile's conversation while fishing is one of the most important scenes in the book, and it centers on that exact question. When Winnie says it would be nice if nothing ever had to die, Miles points out that if so, there'd be so many creatures on the earth, they'd be "squeezed in right up next to each other before long." Miles here is trying to show Winnie that death is natural. When the fish he catches is about to die and Winnie protests, he tells her killing things is the natural way. They let the fish go, but Miles lets her know that it cannot always be that way.
Winnie learns that the Tucks are not only protecting the secret of their immortality for their own sakes, but for the sake of mankind. The love the Tuck family shows Winnie is necessary for Winnie to learn this valuable lesson, which she does. In the end, she chooses life AND death. In the epilogue, Tuck's comment, "good girl," when looking at Winnie's grave, confirms his belief that death is the natural way of the world. Even though he is grief-stricken, he is happy she made the right choice.