Here is a list of important dates you may want to know. Study them and know them. They will be helpful during essays and DBQs as well! SFIs are always helpful to gain extra points on essays.
There are links at the bottom for more info.

1620/11/09 NA - Mayflower lands
1689/05/12 WR - King William's War begins
1697/09/30 WR - King William's War ends (Peace of Ryswick)
1702/05/04 WR - Queen Anne's War begins
1713/04/11 WR - Queen Anne's War ends (Peace of Utrecht)
1744/03/15 WR - King George's War begins
1748/10/18 WR - King George's War ends (Treaty of Aix-la-Chapelle)
1754/07/10 NA - The Albany Congress meets
1754/07/03 WR - French and Indian War begins
1763/02/10 WR - French and Indian War ends (Treaty of Paris)
1770/03/05 NA - Boston Massacre
1774/09/05 NA - First Continental Congress convenes
1775/04/18 WR - American Revolution begins
1775/05/10 NA - Second Continental Congress convenes
1776/07/04 NA - Declaration of Independence adopted
1776/12/20 NA - Third Continental Congress convenes
1777/11/15 NA - Articles of Confederation proposed
1781/03/01 NA - Articles of Confederation ratified
1783/02/04 WR - English declare hostilities at an end
1783/04/11 WR - America declares hostilities at an end
1784/01/14 WR - Revolutionary War Ends (Treaty of Paris)
1787/05/25 NA - Constitutional Convention opens
1787/09/17 NA - Final draft of the Constitution sent to Congress
1787/12/07 SH - Delaware
1787/12/12 SH - Pennsylvania
1787/12/18 SH - New Jersey
1788/01/02 SH - Georgia
1788/01/09 SH - Connecticut
1788/02/06 SH - Massachusetts
1788/04/28 SH - Maryland
1788/05/23 SH - South Carolina
1788/06/21 SH - New Hampshire
1788/06/21 NA - Constitution Ratified
1788/06/25 SH - Virginia
1788/07/26 SH - New York
1789/03/04 NA - The Constitution goes into effect
1789/04/30 PR - George Washington
1789/07/14 NW - French Revolution
1789/09/25 AP - Amendments 1-10, 27, one unratified amendment
1789/11/21 SH - North Carolina
1790/05/29 SH - Rhode Island
1791/03/04 SH - Vermont
1791/12/15 AR - Amendments 1-10
1792/06/01 SH - Kentucky
1794/03/04 AP - Amendment 11
1795/02/07 AR - Amendment 11
1796/06/01 SH - Tennessee
1797/03/04 PR - John Adams
1801/03/04 PR - Thomas Jefferson
1803/03/01 SH - Ohio
1803/12/09 AP - Amendment 12
1804/06/15 AR - Amendment 12
1809/03/04 PR - James Madison
1810/05/01 AP - Unratified anti-title amendment
1810/09/16 NW - Mexican independence
1812/04/30 SH - Louisiana
1812/06/18 WR - War of 1812 begins
1814/12/24 WR - War of 1812 ends (Treaty of Ghent)
1815/06/18 NW - Battle of Waterloo  (end of Napoleonic Wars)
1816/12/11 SH - Indiana
1817/03/04 PR - James Monroe
1817/12/10 SH - Mississippi
1818/12/03 SH - Illinois
1819/12/14 SH - Alabama
1820/03/15 SH - Maine
1821/08/10 SH - Missouri
1825/03/04 PR - John Quincy Adams
1827       NW - Greek Independence
1829/03/04 PR - Andrew Jackson
1836/06/15 SH - Arkansas
1837/01/26 SH - Michigan
1837/03/04 PR - Martin Van Buren
1839       NW - First Opium War begins
1841/03/04 PR - William Harrison
1841/04/04 PR - John Tyler (following death of Harrison)
1842/08/29 NW - First Opium War ends (Treaty of Nanking)
1842/08/29 NW - Hong Kong ceded to Britain
1845/03/03 SH - Florida
1845/03/04 PR - James Polk
1845/12/29 SH - Texas
1846/04/25 WR - Mexican War begins
1846/12/28 SH - Iowa
1848       NW - Communist Manifesto published
1848       NW - Revolutions in Germany, Austria, France, Italy, Belgium
1848/02/02 WR - Mexican War ends (Treaty of Guadalupe Hidalgo)
1848/05/29 SH - Wisconsin
1849/03/04 PR - Zachary Taylor
1850/07/09 PR - Millard Fillmore (following death of Taylor)
1850/09/09 SH - California
1853/03/04 PR - Franklin Pierce
1857/03/04 PR - James Buchanan
1858/05/11 SH - Minnesota
1859/02/14 SH - Oregon
1860/12/20 NA - South Carolina votes to secede
1861/01/09 NA - Mississippi votes to secede
1861/01/10 NA - Florida votes to secede
1861/01/11 NA - Alabama votes to secede
1861/01/19 NA - Georgia votes to secede
1861/01/26 NA - Louisianna votes to secede
1861/01/29 SH - Kansas
1861/02/01 NA - Texas votes to secede
1861/03/02 AP - Unratified slavery amendment
1861/03/04 PR - Abraham Lincoln
1861/03/11 NA - Confederate Constitution ratified
1861/04/12 WR - Civil War begins (Fort Sumter)
1861/04/17 NA - Virginia votes to secede
1861/05/06 NA - Arkansas votes to secede
1861/05/20 NA - North Carolina votes to secede
1861/06/08 NA - Tennessee votes to secede
1861/10/31 NA - Missouri votes to secede
1861/11/20 NA - Kentucky votes to secede
1863/06/20 SH - West Virginia
1864/10/31 SH - Nevada
1865/01/31 AP - Amendment 13
1865/04/08 WR - Civil War ends (Lee surrenders to Grant)
1865/04/15 PR - Andrew Johnson (following death of Lincoln)
1865/12/06 AR - Amendment 13
1866/06/13 AP - Amendment 14
1866/07/24 NA - Tennessee readmitted to the Union
1867/03/01 SH - Nebraska
1868/02/24 NA - House impeaches President Johnson
1868/05/16 NA - Senate acquits President Johnson
1868/06/22 NA - Arkansas readmitted to the Union
1868/06/25 NA - Florida readmitted to the Union
1868/07/04 NA - North Carolina readmitted to the Union
1868/07/09 NA - South Carolina readmitted to the Union
1868/07/09 NA - Louisiana readmitted to the Union
1868/07/09 AR - Amendment 14
1868/07/13 NA - Alabama readmitted to the Union
1869/02/26 AP - Amendment 15
1869/03/04 PR - Ulysses Grant
1870/01/26 NA - Viginia readmitted to the Union
1870/02/03 AR - Amendment 15
1870/02/23 NA - Mississippi readmitted to the Union
1870/03/30 NA - Texas readmitted to the Union
1870/07/15 NA - Georgia readmitted to the Union
1871/10/08 NA - Great Chicago Fire
1876/08/01 SH - Colorado
1877/01    NW - Russo-Turkish War begins
1877/03/04 PR - Rutherford Hayes
1878/06    NW - Russo-Turkish War end (Treaty of San Stefano)
1881/03/04 PR - James Garfield
1881/09/19 PR - Chester Arthur (following death of Garfield)
1885/03/04 PR - Grover Cleveland
1889/03/04 PR - Benjamin Harrison
1889/11/02 SH - North Dakota
1889/11/02 SH - South Dakota
1889/11/08 SH - Montana
1889/11/11 SH - Washington
1890/07/03 SH - Idaho
1890/07/10 SH - Wyoming
1893/03/04 PR - Grover Cleveland
1893/06/27 NA - Stock market crash
1896/01/04 SH - Utah
1897/03/04 PR - William McKinley
1898/04/21 WR - Spanish-American War begins
1898/12/10 WR - Spanish-American War ends (Treaty of Paris)
1898/12/10 NA - Guam, Puerto Rico ceded by Spain
1899/10/12 NW - Boer War begins
1901/09/14 PR - Theodore Roosevelt (following death of McKinley)
1902/05/31 NW - Boer War ends
1904/02/08 NW - Russo-Japanese War begins
1905/09/05 NW - Russo-Japanese War ends
1906/04/18 NA - Great San Francisco Earthquake
1907/03/13 NA - Stock market crash
1907/11/16 SH - Oklahoma
1909/03/04 PR - William Taft
1909/07/12 AP - Amendment 16
1912/01/06 SH - New Mexico
1912/02/14 SH - Arizona
1912/02/12 NW - End of China's Qing Dynasty
1912/04/15 NW - Titanic sinks
1912/05/13 AP - Amendment 17
1913/02/03 AR - Amendment 16
1913/03/04 PR - Woodrow Wilson
1913/04/08 AR - Amendment 17
1913/10/10 NW - Panama Canal completed
1914/06/28 NW - Archduke Ferdinand assassinated, setting off WWI
1917/03/15 NW - The Tsar of Russia abdicates
1917/03/31 NA - U.S. purchases the Virgin Islands from Denmark
1917/12/18 AP - Amendment 18
1918/04/02 WR - United States joins WWI
1919/01/16 AR - Amendment 18
1919/06/04 AP - Amendment 19
1919/06/28 WR - WWI officially ends (Treaty of Versailles)
1920/08/18 AR - Amendment 19
1921/03/04 PR - Warren Harding
1923/08/02 PR - Calvin Coolidge (following death of Harding)
1926/06/02 AP - Unratified child labor amendment
1929/03/04 PR - Herbert Hoover
1929/10/29 NA - Stock market crash
1932/03/02 AP - Amendment 20
1933/01/23 AR - Amendment 20
1933/02/20 AP - Amendment 21
1933/03/04 PR - Franklin Roosevelt
1933/12/05 AR - Amendment 21
1936/07/18 NW - Spanish Civil War
1939/09/03 NW - WWII begins
1941/12/11 WR - United States joins WWII
1945/04/12 PR - Harry Truman (following death of Roosevelt)
1945/09/02 WR - WWII ends
1946/01/10 NW - First meeting of the UN
1947/03/21 AP - Amendment 22
1947/08/15 NW - Indian and Pakistani Independence
1949/10/01 NW - Communist China established
1950/06/25 WR - Korean War begins
1951/02/27 AR - Amendment 22
1953/01/20 PR - Dwight Eisenhower
1953/07/27 WR - Korean War ends
1957/10/04 NW - USSR launches Sputnik
1959/01/03 SH - Alaska
1959/08/21 SH - Hawaii
1960/06/17 AP - Amendment 23
1961/01/20 PR - John Kennedy
1961/04/17 NW - Bay of Pigs invasion
1961/03/29 AR - Amendment 23
1962/08/27 AP - Amendment 24
1962/10    NA - Cuban Missile Crisis
1963/11/22 PR - Lyndon Johnson (following death of Kennedy)
1964/01/23 AR - Amendment 24
1964/08/07 WR - Vietnam War begins (Gulf of Tonkin Resolution)
1965/07/06 AP - Amendment 25
1967/02/10 AR - Amendment 25
1969/01/20 PR - Richard Nixon
1971/03/23 AP - Amendment 26
1971/07/01 AR - Amendment 26
1972/03/22 AP - Unratified equal rights amendment
1973/03/29 WR - Vietnam War ends (last U.S. troops leave Vietnam)
1974/08/09 PR - Gerald Ford (following resignation of Nixon)
1977/01/20 PR - James Carter
1978/08/22 AP - Unratified D.C. voting rights amendment
1979/11/04 NW - Iranian militants seize U.S. embassy
1981/01/20 PR - Ronald Reagan
1982/06/30 NA - Unratified equal rights amendment expires
1985/08/22 NA - Unratified D.C. voting rights amendment expires
1989/01/20 PR - George H. W. Bush
1990/10/03 NW - Reunification of Germany
1991/01/17 WR - Gulf War begins
1991/02/27 WR - Gulf War ends
1992/01/01 NW - USSR dissolved
1992/05/07 AR - Amendment 27
1993/01/20 PR - William Clinton
1998/12/19 NA - House impeaches President Clinton
1999/02/12 NA - Senate acquits President Clinton
1999/03/24 WR - Kosovo Conflict begins
1999/06/10 WR - Kosovo Conflict ends
2001/01/20 PR - George W. Bush
2001/09/11 NA - Terrorists attack New York and Washington D.C.
2001/09/14 WR - Congress authorizes use of force for war on terrorism
2003/03/19 WR - Second Gulf War begins
2003/05/01 WR - Second Gulf War ends (combat operations cease)

More dates and timelines can be found at:

Google Directory
Apush Review
History Timeline
Handouts
Timeline
Infoplease
US History Timeline