In sunny Paw Paw, Michigan, the members of the Spoonapple Repertory Theatre introduce themselves as thirteen-year-old Edwina, advice-giver extraordinaire and director of the group, tries to ready them for the day's performance ("Paw Paw, Michigan"). She reminds them that today is "the" day, the day that the talent scout from the Kalamazoo Advice-a-Palooza Festival will be in the Paw Paw audience, looking to fill a final festival spot!

When Edwina gets news that one of the Spoonapple Rep members has been injured in a sledding accident, she tries to convince her new next-door neighbor, Bobby, to join their troupe as a last-minute replacement. She sadly reveals to a reluctant Bobby that, while her siblings, Katie, Myra and Joe, all have prizes for their various achievements tacked up on the family fridge, Edwina has nothing to show for her own talent of giving advice. However, if she can get an invitation to the Kalamazoo festival, she will finally have something of her own of which to be proud ("Up on the Fridge"). Bobby is convinced to help out.

Edwina makes her show entrance in a wheelbarrow filled to the brim with letters ("Dear Edwina"). In the first letter, Edwina is asked what to do about Hephaestus' little brother, Aristotle (played by Billy), who constantly refuses to eat the delicious foods that his mother serves him ("Hephaestus"). Edwina, with help from that fabulous rock group, Susie and the Napkins (a.k.a. Annie and the rest of the kids), demonstrates how a similar little boy named Johnny learned the trick to being polite ("Say No Thank You").

Edwina cues Scott to bring out the next letter but, as he hands her the letter, Edwina immediately notices that it isn't the one they rehearsed. Everyone knows that he's in love with Edwina, so she fears for what the letter might contain ("Another Letter!"). Over Scott's protests, Edwina reads the audience a letter by Abigail instead, who wants to know how to make her brother stop acting like an "obnock" before her upcoming birthday party ("Abigail"). The answer is given by Edwina's scary Uncle Vladimir (a.k.a. Billy) of Transylvania, who tells the story of the rudest, most rambunctious guest in the world, who was finally cured when everyone stopped paying him any attention ("Frankenguest").

Scott again tries to substitute his own letter for the next one that they have rehearsed. However, he is foiled by Kelli, who brings Edwina a postcard from her summer camp friend, Carrie (a.k.a. Kelli). Carrie has a serious problem: she was asked by her grandmother to set the table but, unfortunately, she has no idea where each utensil should go ("Carrie"). Luckily, Edwina has the answer – in fact, she has composed a whole opera on the do's and don'ts of setting the table ("Fork, Knife, Spoon").

As intermission is announced ("Time for Intermission"), the audience is invited to Kelli's lemonade stand as Scott pleads with Edwina to read his letter. However, Edwina, along with the rest of the kids, is more interested in finding the talent scout. After searching through the crowd, they soon notice a woman with the Kalamazoo Advice-a-Palooza baseball cap – and she's sleeping! Alarmed, they try to start the second act number about Lola, the shy girl from Peru who learns the importance of saying hello ("Here Comes More Letters / Hola Lola") loudly and with a bang.

As Scott again tries in vain to give Edwina his letter, Billy interrupts him with a calypso yell, pulling him into the next scene. They are transformed into the steel drum section of the Paw Paw marching band, hoping to participate in the big steel drum parade happening in Jamaica ("Ziggy"). Ziggy (played by Billy) tells Edwina that, while they worked hard to raise money for their trip, holding bake sales, car washes, etc., they then spent every cent at a sale down at the mall. What to do? Edwina advises them on the importance of saving for a rainy day as her cousin, Mary Sue Betty Bob (a.k.a. Annie), demonstrates how to be careful with your nickels ("Put It in the Piggy").

Edwina endeavors to bring the show to a close ("Thanks for Coming I"), but Scott refuses to end it, insisting upon reading his letter. Before Edwina can stop him, Scott begins to sing about the girl he loves, whose name he has carved into a heart in his dad's woodshop – the lovely Edwina herself ("Edwina"). Edwina begs Scott not to embarrass himself, but Scott insists that he will not be denied. The kids, impressed with Scott's persistence, sing backup as he waxes poetic about his beloved. Finally, full of newfound bravado, Scott throws Edwina over his shoulder, uttering the four winning words: "You! Me! Dairy Queen!"

As the kids end the show ("Thanks for Coming II") and congratulate Scott, the phone rings: it is Ann Van Buren from the Kalamazoo Advice-a-Palooza Festival! The talent scout announces that, after what she just heard, there is a definite spot in the festival – for Scott! Edwina is crushed ("Up on the Fridge Breakdown") and wonders if she'll ever have something up on the family fridge when suddenly, her little sister, Katie (played by Kelli), enters crying. Katie tells Edwina that she has run away from the Summer Math Olympics because, when she finished her equations first, two of her competitors made fun of her. Edwina comforts her sister, advising her that she must always remember to do her own thing and be unafraid of achieving her dreams ("Sing Your Own Song"). Katie agrees to go back to the Olympic Village, and Edwina's friends enter, telling Edwina that she gives the best advice of all and that perhaps she should follow her own advice. Edwina happily realizes that, while she may not have an invitation to put up on the fridge, a hug from her sister is a better reward, and that, if you do what you love, that's the best thing of all ("Up on the Fridge – Reprise").