Speed cameras are officially back on in New York City and just in time for the beginning of the school year.

Mayor Bill de Blasio signed the bill putting the cameras back in action today.

"Intro. 1089 revives our lifesaving school speed camera program just in time for the first day of class,” says Mayor de Blasio. "By a stroke of a pen today, we are going to set things right.”

The state Assembly worked to take action on speed cameras, but the state Senate never brought the bill to the floor for a vote.

As a result, Mayor de Blasio, the City Council and Gov. Andrew Cuomo all worked together to find a legislative solution to get the cameras back.

The law will be immediately enforced at 140 schools where speed cameras are already up.

The city will also be expanding the use of speed cameras to an additional 150 schools.

Amy Cohen, who lost her son in a traffic crash in 2013, has supported the cameras for years.

“Many of you heard me talk about Sammy, for nearly five years. You have heard me describe what loss means to a parent whose child has died,” says Cohen.

City Council Speaker Corey Johnson says stories like Cohen’s made the speed camera issue a pressing one.

“Thank you for channeling your unspeakable tragedies into action and results that will save lives. This is why I ran for office, thank you,” says Johnson.

While city officials were praised for the hard work that went into the bill, Cohen had someone special to thank as well.

"I would also like to thank my brave son who was on the cusp of becoming a young man named Sam, but who died still as a child named Sammy, he inspires me every single day,” says Cohen.