The Chicago Teacher’s Union (CTU) is using ideas from the University of Chicago Laboratory Schools to form a response to Mayor Rahm Emanuel’s call for longer days in Chicago public schools.

The CTU is considering whether to extend the school day by 75 minutes, putting that time toward specialized subjects like world languages, music, art, and physical education in a curriculum partially inspired by one implemented at the Lab Schools, which are private.

The CTU is presenting its plan as an alternative to a pilot program launched by Emanuel and Chicago Public Schools (CPS) CEO Jean-Claude Brizard. Nine public schools have entered into the CPS program, which offers incentives to schools for adding 90 minutes to their school day.

“[Our suggestion] is making a change that wasn’t as dramatic as CPS’s proposal,” Carol Caref, a coordinator for the CTU’s professional development wing, said.

The Lab Schools’ model is designed to form well-rounded students from an early age, according to Lab Schools Director David Magill. Magill added that the schools were not involved in the development of the union’s plan.

Caref said that the union has looked at many other schools as it sought to draft an acceptable plan for extending the school day.

The CTU plan would also give teachers two daily, 45-minute periods for lesson planning, Caref said.

The 75-minute extension is still in its planning stages, although Caref said that the CTU may put it on the table when they negotiate with CPS next summer.