The year comes to a close with graduation looming on the horizon for five students, four older girls and, of course, Royce. At school, all the students are involved in planning the all-school party.
Things are a-changing, and even Miss Butler is now wearing a tiny engagement ring that she got from Arnold.
In the middle of what starts out as a perfectly normal, sunny school day, the tornado siren goes off. The students are shuffled down to the basement. Instead of following everyone, Mary Alice breaks loose and runs home because she wants to make sure that Grandma is all right.
By the time she gets back to the house, rain is pouring down. Grandma takes one look at her and tells her to go to the southwest corner of the house, which is where the cellar is located.
Grandma enters the cellar too, bringing Bootsie and the kitten. They sit and wait, and then hear the deafening sound of the wind whooshing and the tacks coming out of the tar paper on the roof. All they can do is duck down and wait for it to pass.
As soon as the storm blows over, Grandma and Mary Alice leave the house with tools and gloves in tow. Walking around, they can see that lots of trees have fallen over, chimney bricks are lying around, and other people are just starting to come out of their own homes.
They make their way to Old Man Nyquist's house, which isn't looking too great. They can see through the roof, the porch is gone, and when they enter, they find Nyquist stuck underneath his bedstead.
Using a crowbar, they get him unstuck, but Old Man Nyquist is far from grateful. The entire time, he and Grandma yell insults at each other.
As they leave, Mary Alice remarks on how mean Nyquist is, but Grandma just says that no one else would come near enough to help him—which is why they did it.
They go to check on Mrs. Wilcox's house, which looks okay. But when they see that the privy's blown away, Grandma gets worried.
Just then, Mrs. Wilcox shows up. Turns out she was pretty nervous during the tornado and she really needed to "go," but her privy was already gone. So she went over and used Grandma's.
Grandma and Mary Alice head home, and Mary Alice asks Grandma if she and Mrs. Wilcox are besties. Grandma says that they're just neighbors. Mmm-hmm. Mary Alice is pretty sure she knows better.
After the tornado, Grandma becomes obsessed with cleaning up the house, even though there's only her and Mary Alice living there. Arnold's gone back to New York City to wait for Miss Butler to join him.
Then graduation rolls around, and Royce is named valedictorian. He also gets a scholarship to the University of Illinois at Champaign, which is super exciting.
At the all-school party, Mary Alice and Royce get a moment to themselves for the first time since that disastrous math tutoring date. Royce asks Mary Alice if he can write to her while he's in college, and she promises to write back. Sweet.
When Mary Alice gets home that night, she tells her Grandma that she wants to stay, even though her parents have just written. Her father's gotten a job and they have an apartment that's big enough to accommodate Mary Alice now…but Mary Alice worries about her grandmother.
Grandma immediately says that she can't stay, and that she needs to rent out Mary Alice's room. Of course, Mary Alice knows the truth. Her grandmother likes having her here, but she doesn't want Mary Alice to stay out of guilt or worry.
In the end, Grandma tells Mary Alice to go back to Chicago and to take Bootsie's kitten with her; in the meantime, Grandma will be here with Bootsie. And Mary Alice can come back to visit whenever she wants.