When Karen Lewis and the Chicago Teachers Union suspended negotiations with the city last week to go on strike, they did so at the expense of 350,000 public school students, who have already missed more than a week of classes.

The strike, which is the CTU’s first in 25 years, is in protest of reasonable school reforms such as using student test performance as a partial factor in teacher evaluations and the process in which laid off teachers must go through in order to be rehired. While Chicago Mayor Rahm Emanuel, who leads the city’s push for reform, wants the school principals to make the rehiring decisions, the union prefers a “recall” system, which gives laid-off teachers automatic priority over new openings.

Many of the policies being proposed have already been implemented widely throughout the nation, and low-performing Chicago public schools risk being left behind as the wave of sensible school reforms continue to be implemented elsewhere.

Even while tension remains high, the two sides are relatively close to agreeing on a contract, which makes the strike all the more unnecessary. Emanuel and Lewis have already agreed to extend the school day while hiring an additional 477 new teachers.

Despite Lewis calling the most recent proposal “a good contract” Saturday night, the teachers have not called off the strike, increasing the total number of class days students have been forced to miss.

Teachers unions are often wrongly blamed for failing schools. While the CTU is not the cause of low performance in Chicago’s public schools, they cannot act as barriers to sensible reforms.