FILE - In this May 28, 2013, file photo, an outdoors sign for Walmart is seen in Duarte, Calif. After enduring a severe winter that chilled business, Wal-Mart is trying to lure shoppers into its stores with the biggest weapon in its arsenal: a big sale. The worldâs largest retailer is offering up to 50 percent on more than 60 outdoor items such as lawn mowers and bags of mulch, starting Friday, March 21, 2014, and ending the following Saturday. (AP Photo/Damian Dovarganes)

WASHINGTON -- Kicking off the third consecutive year of protests, Walmart workers in six states have formally submitted strike notices to their bosses ahead of the Black Friday shopping frenzy, calling for higher wages and better hours, according to OUR Walmart, the group representing the workers.

OUR Walmart did not provide an estimate on how many workers planned to take part in the strikes this year. It did, however, say that workers in Wisconsin, Louisiana, Florida, California, Maryland, Virginia and Washington, D.C., have already delivered notices, and it anticipates workers in Illinois, Minnesota, Texas and Pennsylvania will do so as well.

Charles Brown, an OUR Walmart member who unloads trucks at a Walmart in Newport News, Virginia, said he plans to miss three shifts this week to take part in the demonstrations. Brown said he joined the group in September to demand a greater say in scheduling as well as "more respect" from management.

"Some [other workers] may want to do a strike as well but are hesitant," said Brown, 27. "They need to know they don't have anything to be afraid of. If we don't stand up, no one else is going to stand up for us."

Black Friday has become an annual rallying cry for the anti-Walmart crowd, with labor activists and other progressives pillorying the world's largest retailer over its wages and scheduling practices for store employees. It also marks the most contentious week of the year between the Arkansas-based retail giant and OUR Walmart, which is backed by the United Food and Commercial Workers, a union that's been working to organize Walmart employees for years.

Walmart has downplayed the significance of the strikes in years past, noting that they involve just a tiny fraction of the retailer's one-million-plus U.S. workforce, and painted them as union-orchestrated stunts. OUR Walmart tends to put the number of strikers in the hundreds each year, while Walmart puts it more in the dozens.

"Perception is not reality in this case," said Brooke Buchanan, a Walmart spokeswoman. "Year after year we see the labor union and paid organizers promising they'll be out in force. And every year, we see a handful of people at a handful of stores."

Noting that Walmart workers get a holiday bonus, Buchanan also threw this barb at OUR Walmart and UFCW: "Are they going to pay their workers double time for working the holiday?" A union spokeswoman said all employees are salaried and work "as needed," meaning there is no bonus.

The sight of Walmart workers going on strike in the past two years has provided a shot in the arm to the labor movement, even if the numbers aren't large enough to impact sales. Like the fast-food walkouts that have popped up in cities across the country, the Walmart strikes aren't necessarily meant to disrupt the company's operations, but instead to draw attention to the participants' grievances.

This year, the group's members are making a specific demand in the protests: a wage of $15 and "consistent, full-time hours." Not coincidentally, $15 per hour is the same demand being put forth by the fast food strikers, whose movement is billed as Fight for $15 and who are backed by the Service Employees International Union.

OUR Walmart members have also been calling for an end to what they describe as retaliation from management for speaking out.

Since the strikes began in 2012, UFCW has filed a host of unfair labor practice charges against Walmart with the National Labor Relations Board, some of which the board's general counsel found merit in, some of which it did not. The general counsel issued a complaint in January alleging that Walmart had illegally punished workers in several states surrounding the strikes. That case has not yet been resolved.

OUR Walmart, in turn, has faced a number of court injunctions barring its members from protesting on Walmart property in certain states due to trespassing.

Many of the protests have focused on a lack of stable hours for workers, who say they don't get enough time on the schedule in order to make ends meet. Walmart says that a majority of its workforce is full-time, though it doesn't provide an exact percentage. The company recently launched a program aimed at giving more hours to the workers who need them, though it insisted the program was not a response to the protests.

Glova Scott, an employee at a Walmart in Washington, D.C., said she has already called in to her store and told them she won't be coming in this week. Scott said she's been working for Walmart for a little over a year but just joined OUR Walmart a week and a half ago. Fifty-nine years old, she earns $10.90 an hour stocking shelves on the night shift.