![Chicago teachers walk the picket line outside the headquarters of Chicago Public Schools in Chicago September 10, 2012. Thousands of public school teachers formed picket lines in Chicago on Monday and parents Chicago teachers walk the picket line outside the headquarters of Chicago Public Schools in Chicago September 10, 2012. Thousands of public school teachers formed picket lines in Chicago on Monday and parents](https://c8.alamy.com/compfr/2e697hh/chicago-teachers-walk-the-picket-line-outside-the-headquarters-of-chicago-public-schools-in-chicago-september-10-2012-thousands-of-public-school-teachers-formed-picket-lines-in-chicago-on-monday-and-parents-scrambled-for-child-care-during-their-first-strike-in-a-quarter-century-over-reforms-sought-by-mayor-rahm-emanuel-and-endorsed-by-president-barack-obamas-administration-reuters-jeff-haynes-united-states-tags-civil-unrest-education-politics-2e697hh.jpg)
Chicago teachers walk the picket line outside the headquarters of Chicago Public Schools in Chicago September 10, 2012. Thousands of public school teachers formed picket lines in Chicago on Monday and parents
![Amazon.com: New York Picket Line 1960 Npicket Line In Front Of The Woolworth Building In New York City 14 April 1960 The Majority Of The Picketers Are Ministers Protesting The StoreS Lunch Amazon.com: New York Picket Line 1960 Npicket Line In Front Of The Woolworth Building In New York City 14 April 1960 The Majority Of The Picketers Are Ministers Protesting The StoreS Lunch](https://m.media-amazon.com/images/I/71UDZrqIZCL._AC_SL1000_.jpg)
Amazon.com: New York Picket Line 1960 Npicket Line In Front Of The Woolworth Building In New York City 14 April 1960 The Majority Of The Picketers Are Ministers Protesting The StoreS Lunch
![The first picket line - College day in the picket line. Women suffragists picketing in front of the White house. Date 1917 Feb Stock Photo - Alamy The first picket line - College day in the picket line. Women suffragists picketing in front of the White house. Date 1917 Feb Stock Photo - Alamy](https://c8.alamy.com/comp/ER9ACD/the-first-picket-line-college-day-in-the-picket-line-women-suffragists-ER9ACD.jpg)