Janet and Ben have made a pact to eat a full bag of marshmallows each when they turned 18, but knowing they may not live that long, they decide to do it today. They each stuff several marshmallows in their mouth at a time and finish their bag without issue. They jump on the trampoline and play with balloons, and then Janet starts thinking about Mrs. Ezra’s apple tree. She’s always wanted to try one, but she’s heard that their neighbor is a witch who curses her apples. Janet imagines herself turning into a troll and decides against the idea, but Ben starts to think of ways to make it come true.

Janet thinks about something she has been putting off, and decides to do it since it might actually be her last day. She pulls a latch hook set out of the closet and shows Ben how to work the latch hook and follow the key to make a rug. Ben actually finds it enjoyable, but Janet looks like she’d rather be doing just about anything else.

Ben sees his mom’s car drive up and realizes he hasn’t vacuumed, so he dashes home. On his way, he passes his neighbor Mr. Hoggenweff’s hedge and decides that today will be the day he jumps over it. Just as Ben is about to jump, he sees his grouchy neighbor standing in his yard and stops in his tracks, running past the hedge instead of over it. The illustration shows a tornado following Ben home, as though he’s outrunning a disaster.

Ben’s mom comes home in distress. She says that the cake she and Ben’s father had for their wedding was a special cake that her great aunt made, and that the recipe is too complicated for her to understand. Ben doesn’t understand it either, but he promises to help. He googles words like “clabber” and “fold” to figure out how to make the recipe work, and separates the eggs (with a few pieces of shell mixed in). Ben’s mother uses baking soda instead of baking powder and tartar sauce instead of cream of tartar. The result is a stinky, slimy mess, but they bake it anyway and hope for the best. Once the cake is in the oven, Ben reflects that he never knew how much he wanted to bake a cake with his mom. He writes it on his list and then crosses it off.

Ben and his mother wait, staring intently at the oven. Ben vacuums until the cake is ready. The cake is a disaster, and Ben again tries to cheer up his mom. She suggests going to buy a cake that is already made, and tells Ben that he has to do something he won’t like, but which will be good for him, nevertheless. Ben scowls, already intuiting what his mother is about to say.

Ben’s mother tells him he needs to apologize to his classmate Mona, whom he accidentally hit with a Wiffle ball a few days ago. Ben hates the idea of apologizing, especially for an accident, but he knows there’s no point in arguing with his mother about it. When Ben’s mother leaves to buy a new cake, Ben goes to Mona’s house, but he’s greeted by Mona’s mother, who thinks Ben is back to injure her daughter again. He assures her he isn’t, and when Mona comes to the door with a bandage on her head but no visible wound, Ben puts aside his pride and apologizes to her. Ben tells Mona he was aiming for Janet in a game they were playing, and Mona demands to hear this firsthand from Janet.

After going to Janet’s house and confirming Ben’s story, Mona still isn’t satisfied, so Ben tells her it could be her last day on earth. Mona looks suddenly panicked, but decides that she would like to take advantage of this last day to ride Ben’s scooter. Ben shows her how to ride it, and with a look of determination on his face, successfully performs his first “tail whip” trick. All this impresses Mona, who is eager for her turn.

Mona is doing well on the scooter until she decides she wants to try Ben’s fancy tail whip trick. Ben’s eyes widen, and he tries to stop her, but Mona doesn’t listen and goes for it anyway. She flips around and into the air, and then tumbles down and hurts herself. Mona’s mother appears, livid, but Mona forgives Ben, and he checks the apology and the scooter trick off his list.