My 6-year-old daughter, Scarlett, is a first-grader at A.N. Pritzker Elementary, one of 600 schools in the Chicago Public Schools system. Scarlett enjoys reading, but she has recently faced a serious problem getting the books she wants. The Chicago Teachers Union is preventing her and her classmates from using the school library.

Due to a combination of budget cuts and enrollment numbers that were lower than expected, Pritzker’s librarian was laid off shortly after this school year began. Without a librarian, Pritzker students...