By Mark Abrams and Syma Chowdhry

PHILADELPHIA (CBS) — Fast food workers demanding a $15-per-hour minimum wage marched down Broad Street at noontime today, blocking traffic and chanting, eventually converging on a McDonald’s restaurant at Broad and Arch Streets.

“We can’t survive on $7.25. What do we want? $15! When do we want it? Now!” they shouted.

It’s part of a national grass-roots movement called “Fight for $15.”

“Need food on the table, clothes on our back…it’s hard,” said worker Terrell Wesley.

Rasheeda Austin agreed. She said she works three jobs and only makes $11,000 a year.

She also says it is nearly impossible to support a family with her wages.

“Take care of my daughter, put food on the table, clothes on her back, make sure she has everything she needs and don’t ever have to ask anybody for anything,” she said.

Following speeches, dozens of protesters sat down in the middle of Arch Street at Broad, singing “We Shall Not Be Moved.”

They carried signs demanding a $15-per-hour wage and union representation, saying they cannot live on the current minimum wage for fast-food workers, which is $7.25 per hour.

“We deserve more, we work harder — we work harder than the managers. It takes a crew, it takes a team,” said Olivia Smith, another protester.

“This is an on-going fight and we will do whatever it takes to get what we need,” she added.

The workers emphasized they are doing their best to make an honest living.

McDonald’s put out a statement on Thursday saying they believe in paying their employees fair wages, but they also said:

“We believe that any minimum wage increase should be implemented over time so that the impact on owners of small and medium-sized businesses – like the ones who own and operate the majority of our restaurants – is manageable.”

Eleven of the approximately 100 demonstrators were arrested for refusing to disperse after being ordered to do so by Philadelphia police.

Similar orchestrated protests were being held today in cities throughout the United States.