Salom Abdulle is worried her 13-year-old daughter won’t speak Somali, potentially straining her family relationships. “I don’t have any problem understanding my daughter, but my parents do,” she said.

As Jibril Ahmed walked out of his final exam — a math test — he breathed a sigh of relief. “I think I did OK, but I’m so happy to be done,” said Ahmed, 20, cracking a wide smile outside of the ...