There are several symbols in "Tuck Everlasting," including the bottle of spring water, the toad, the music box, the pond and the rowboat, the trout, the wheel and overall religious allegory, according to Shmoop. The main character, Winnie, is given the water bottle filled with spring water that would enable her to live forever. This bottle of water represents both her temptation and her choice.
The toad symbolizes Winnie's desired freedom and her decision on immortality. She gives her chance at immortality to the toad. Maybe she believes a toad would worry less about all of the philosophical and moral dilemmas attached to immortality. The music box, which belongs to Mae Tuck, symbolizes the Tucks' goodness. Winnie is unsure she can trust the Tucks until Mae hands her the music box.
The pond and the moving, living water represents change, growth and life. Tuck explains to Winnie that unlike the water, the Tucks are stuck and unchanging, like the rowboat. They never grow old. He tells her this to explain why choosing to live and grow old is the better choice. The trout they catch also represents Winnie's choice between life and death. She does not want to see the fish die and insists on throwing it back in the pond. There is also the religious symbolism in the story. In some ways "Tuck Everlasting" is a new take on the Garden of Eden where immortality is once again in question. Unlike Eve, Winnie does not give into the temptation, her apple being the water bottle.
Natalie Babbitt from Booksintheclassroom.com highlights one more important symbol in the story: the wheel. The symbol of the wheel is even in the first sentence of the story with a Ferris wheel. Throughout the story, the wheel of life is mentioned or alluded to through symbolism. The Tucks are no longer on the wheel of life; they have fallen off.