Really, what both kids learn is that the other gang members are really pretty much like themselves.
The main thing that Pony learns about the Socs is that they do not feel like they have it made. They feel like they have problems too. He also learns that Cherry, at least, thinks that the Socs are emotionally cold. She says they do not really feel things the way the Greasers do.
I think that Cherry learns mostly that some Greasers are nice like Johnny and Pony, not like all arrogant and somewhat violent like Dally.
Cherry and Ponyboy each learn things about the other's social circle throughout the course of S.E. Hinton's novel The Outsiders. First, they both learn that although they are defined by the groups they associate with by society, there are unique individuals within each of their groups that don't fit society's stereotypes of them. Secondly, they learn that their groups have more in common than they think.
(It is interesting to note that S.E. Hinton capitalizes the word Socs in her novel, but not the word greasers. This shows a sort of societal hierarchy with Socs being of higher rank.)
Most of this learning about each other takes place in chapter two when Ponyboy, Johnny, and Dally meet Cherry Valance and Marcia at the drive-in movies. Dallas Winston, known as Dally, begins taunting Cherry and Marcia, both Socs. Ponyboy and Johnny don't join in the taunting, and Johnny tells Dally to leave the girls alone. When he leaves, they begin talking. Cherry notices the differences between Ponyboy and Johnny, differences that don't fit with the societal stereotype of greasers. She says:
"You two are too sweet to scare anyone. First of all, you didn't join in Dally's dirty talk, and you made him leave us alone. And when we asked you to sit up here with us, you didn't act like it was an invitation to make out for the night."
When Ponyboy describes the gang beating Johnny received from the Socs, Cherry is concerned that Ponyboy thinks that all Socs do things like that. She tells Ponyboy that assuming that all Socs are like the ones who jumped Johnny would be like saying all greasers are like Dallas Winston, and they both know they're not. Ponyboy likes movies, poetry, and sunsets. He and Johnny like to look at the stars. There is a sensitivity in both boys that doesn't fit with society's view of greasers.
Cherry also lets Ponyboy know that Socs do not have the easy carefree life he assumes they do. She says:
"'I'll bet you think the Socs have it made. The rich kids, the West-side Socs. I'll tell you something, Ponyboy, and it may come as a surprise. We have troubles you never even heard of. You want to know something?' She looked me straight in the eye. 'Things are rough all over.'"
Readers learn that the different groups have different value systems. Greasers freely express their emotions, which seems to create deeper bonds of friendship among them. Socs hide their emotions and appear cold and aloof. This type of plasticity gives a superficiality to their relationships not present in the greaser's relationships.
With the revelation that "things are rough all over," Ponyboy realizes the Socs have problems, sometimes similar problems, and not the perfect and carefree life they appeared to have. Throughout the course of the novel, both members of the Socs and members of the greasers become entangled in problems that cause significant harm. Each side must decide whether loyalty to their members or knowledge of what is wrong and what is right will prevail.