The $1.5 billion agreement hammered out by the city and the teachers union still needs approval from the 25,000 members of the union; a vote is expected soon. A contingent of 700 elected delegates issued a tentative acceptance of the agreement on Wednesday.

The agreement stipulates that only five of the 11 days will be made up, tacked on to the end of the school year in June. Teachers will be paid for those five days but not the other six.

The salary increase is 16 percent, to be phased in over five years. The city agreed to place a nurse and a social worker in every city public school within five years and to implement phased hiring of new staff for the neediest schools, with principals making the call on what type of staff is needed.

Another concession won by the union was a guarantee of nap time for children in pre-kindergarten classes.

One contentious element of negotiations that the city ultimately did not budge on was a guarantee of 30 minutes of preparation time for elementary teachers before the day's classes begin, saying that having to pay teachers for that extra time would result in reducing the length of the school day or even the school year. The union had held firm on this demand, an effort to restore something that had been removed during negotiations in the wake of the previous strike, in 2012.

Many student-athletes missed out on state playoffs competitions. As well, many junior missed scheduled PSAT tests and will need to rely on the SAT scores they get in April in order to considered for Merit Scholarships next year.

It was the longest strike in the city since 1987, when a 19-day strike occurred, and the first time that Chicago teachers have gone on strike since 2012.