after it expanded past colleges

[ckok]

Hello, can you explain what the part in bold means?
"Facebook," my son Jake told me, "was my favourite part of high school."...Jake's Class of 2010 was the first to use facebook after it expanded past colleges in 2005. It extended their school life around the clock" (Jeff Jarvis Public Parts)
What is meant by "expanded past colleges?" Thank you

[5jj]

After it grew bigger than when it was used only in colleges.

[ckok]

Thank you so much