I'm wondering if when the US school systems were segregated, were yearbooks segregated as well? Or, if they had like separate schools completely, did people of color even get a yearbook? And upon integration, were colored and non-colored students even featured on the same page in the yearbook?
It's potentially complicated. Some cities had segregated elementary school systems, but integrated secondary schools.
Topeka, Kansas had this situation with at least one high school, Topeka High School, being fully integrated from its start in the 1870s onward (although not quite with all of its extracurricular activities like sports).
It's quite possible that Topeka was an ongoing fight throughout the entire system of segregation (it was originally integrated), because it already had integrated schools on some level in the community. The people against segregation were able to show that integration was possible, and, furthermore, strained community resources as it made them build more schools than necessary. The community didn't have the same deeply entrenched and disenfranchising segregation policies that other cities had. There was room enough to fight back.
http://www.nps.gov/brvb/historyculture/topekasegregation.htm
There's a picture here of integrated Lowman Hill students in 1879. There were some schools that even refused to segregate (Gage School), while others forced it (Potwin- not surprising, Potwin was in a pretty upper class part of town- think Meet Me in St. Louis style). So even then, Topeka had some integrated elementary schools and many that were not.
As for segregated yearbooks, I vaguely recall old Topeka High yearbooks that not only featured all of their students, they featured pictures of their black student union even during this time period.
Other school systems were probably more segregated, but even back then, some segregated school systems still had some integration to a certain extent.
Separate schools have separate yearbooks. So the black high school had its own in that era—though in the early part of the 20th century the students at black schools in rural areas might not have had the money to purchase yearbooks, nor could the school have subsidized that activity.
When integrated, schools took some pains to treat all students equally. This sometimes meant quotas for things like class favorites and officers. Pictures in yearbooks are organized by sports/activities, clubs, and class (year)—not by race. The black students named Johnson were alphabetically in between the white students named Johnson.