23 Apr, 1898 - Spain declares war on the United States
23rd April, 1898 : Spain declares war on the United States on April 23rd, 1898 after rejecting America's ultimatum to withdraw from Cuba. Following the declaration The American Asiatic Squadron under Commodore George Dewey engaged the Spanish Pacific Squadron under Admiral Patricio Montojo y Pasarón in Manila Bay, the Philippines and decimated the Spanish squadron.
Taken from: http://www.thepeoplehistory.com/april23rd.html
22nd April, 1889 : The Oklahoma Land run begins with an estimated 50,000 people lined up at noon hoping to stake a claim for a homestead ( the claim could be up to 160 acres in size ), it included most of the following Oklahoma Counties, Canadian, Cleveland, Kingfisher, Logan, Oklahoma, and Payne ( in total about 2 million acres ). This land had previously been occupied by Indians but the Indian Appropriations Bill approved the transfer of two million acres for settlement.
21st April, 1989 : 100,000 students gather at Beijing's Tiananmen Square to commemorate Hu Yaobang the deposed reform-minded leader of the Chinese Communist Party and voice their discontent with China's authoritative communist government. This was the beginning of the mass demonstrations in Tiananmen Square, Beijing prior to the Chinese Government declaring martial law in May of the same year which led to the June Massacres by Chinese troops killing hundreds of demonstrators and arresting thousands of protesters and other suspected dissidents.
Taken from: http://www.thepeoplehistory.com/april21st.html
Here are the videos I told you guys about. They will help you understand important ideas and concepts.
World War 2 and Japanese Internment
APUSH was restructured 2 years ago, and they made the experiences of minorities crucial to AP US History. So being familiar with Japanese Internment would be good, and it is mentioned in the Key Concept. I showed the shortened version in class, but the full one is worth the watch!
Cold War Beginnings
The video found at YouTube - search Untold History: Stalin, the Soviet Union and WWII - explains nicely Stalin's position during and after WW2. It is an eye opener!
20th April, 1999 : Two students ( Eric Harris and Dylan Klebold ) wearing balaclavas go through Columbine High School in Denver, Colorado, firing automatic weapons and throwing homemade bombs killing 13 people and wounded 24 others before the two students committed suicide. They had originally planted two home made bombs in the cafeteria and were planning on murdering the students as they ran from the building, when the bombs failed to go off they went into the school and began the massacre.
Taken from: http://www.thepeoplehistory.com/april20th.html