If the first thing that's coming to your mind is The Rock—as in the pro-wrestler/actor—we're not going to hold it against you. In fact, The Rock isn't a bad jumping off point because he's all about strength and endurance, which is what rocks and stones symbolize in this book too.
Sure Farewell to Manzanar isn't exactly a Fast and Furious flick, but it is all about the human willpower to endure and overcome really bad things like mass internment, racial/ethnic prejudice, domestic abuse, and poverty.
But okay, we know—you're gonna need some evidence to back this statement up. Let's take a look at Jeanne when she's all grown up and wandering around the ruins of Manzanar. She finds "concrete slabs where the latrines and shower rooms stood, and irrigation ditches, and here and there, the small rock arrangements that once decorated many of the entranceways" (3.1.15).
Let's just pause here for a sec and note that what counts as rocks/stones can range from the memorial obelisk (3.1.12) that honors the dead internees and their gravestones to those concrete slabs (not really stone exactly, but similar in hardness) that mark all those toilets they had to deal with to the rocks the Issei men used to decorate their gardens. Manzanar is basically all rock at this point.
These different kinds of stones point to the different ways histories and memories can endure. Like the latrines: they speak to the horror of camp conditions, so that we never forget how hard camp life was for the Japanese-Americans. And then there are the garden stones, which represent the endurance of human nature and its ability to create beauty out of horror:
I had found out that even in North Dakota, when Papa and the other Issei men imprisoned there had free time, they would gather small stones from the plain and spend hours sorting through a dry stream bed looking for the veined or polished rock that somehow pleased the most. It is so characteristically Japanese, the way lives were made more tolerable by gathering loose desert stones and forming with them something enduringly human. (3.1.15)
See? Just like Jeanne says: stones = the "enduringly human." Inspiring stuff, right?
And she goes on:
These rock gardens had outlived the barracks and the towers and would surely outlive the asphalt road and rusted pipes and shattered slabs of concrete. Each stone was a mouth, speaking for a family, for some man who had beautified his doorstep. (3.1.15)
Narrator Jeanne makes sure we understand that even though there are different types of memories about camp, she's going to rest on the fact that the rock gardens are going to outlive the ugly parts of camp life because the rock gardens show how human nature bends toward the peaceful and the beautiful, even in the face of all that is horrible.
Now that is what we call truly inspiring.