Believe in the possible . . . with this New York Times bestseller by three-time Newbery Honor winner Jennifer L. Holm. A perfect read about a child's relationship with her grandfather!   Galileo. Newton. Salk. Oppenheimer. Science can change the world . . . but can it go too far?   Eleven-year-old Ellie has never liked change. She misses fifth grade. She misses her old best friend. She even misses her dearly departed goldfish. Then one day a strange boy shows up. He’s bossy. He’s cranky. And weirdly enough . . . he looks a lot like Ellie’s grandfather, a scientist who’s always been slightly obsessed with immortality. Could this gawky teenager really be Grandpa Melvin? Has he finally found the secret to eternal youth?   With a lighthearted touch and plenty of humor, Jennifer Holm celebrates the wonder of science and explores fascinating questions about life and death, family and friendship, immortality . . . and possibility. Look for EXCLUSIVE NEW MATERIAL in the paperback—including Ellie’s gallery of scientists and other STEM-appropriate features. And don’t miss the much-anticipated sequel, The Third Mushroom!   “Warm, witty, and wise.” —The New York Times   * “Written in a clean, crisp style, with lively dialogue and wit, this highly accessible novel will find a ready audience.” —Booklist, Starred   * “Top-notch middle-grade fiction.” —Publishers Weekly, Starred   * “Ellie’s memorable journey into the world of science will inspire readers to explore the world around them and celebrate the possible.” —Shelf Awareness, Starred   “Awesomely strange and startlingly true-to-life. It makes you wonder what’s possible.” —Rebecca Stead, Newbery Medal–winning author of When You Reach Me 25 STATE AWARD LISTS including the Sunshine State!