Lesson Plans: Grades 9-12


The Lesson


The dropping of an atomic bomb on the Japanese city of Nagasaki

The dropping of an atomic bomb on the Japanese city of Nagasaki finally persuaded the Japanese to surrender, thus ending the Pacific campaign and World War II.

Credit: Image courtesy of American Memory at the Library of Congress.

The U.S. victory over the Japanese Navy at Midway succeeded in stopping the Axis advance in the Pacific, and by early 1943 the Marines had driven the Japanese from Guadalcanal. Thus began the long, slow process of forcing the enemy out of a series of fortified positions in the Central and South Pacific. The strategy employed was often called "island-hopping" or "leap-frogging"—concentrating on certain critical enemy bases while bypassing others in the hope that, cut off from their supply routes, they would "wither on the vine," as the American commander, Douglas MacArthur, put it. By early 1945 the noose was tightening around Japan itself, as Allied forces captured islands close enough to be used as airbases for bombing raids against Japanese cities. One by one the largest cities in Japan were hammered from the air—a strategy that culminated in the use of the first atomic bombs, at Hiroshima and Nagasaki, in August 1945. The government in Tokyo announced its surrender soon thereafter, bringing World War II to an end.

This lesson will guide students through the military campaigns of the Pacific theater, tracing the path of the Allied offensives. Through an examination of historical documents and the use of an interactive map, students will gain an understanding of what the Allies were trying to accomplish, and why. Moreover, they will consider the controversial issue of the use of atomic bombs on Hiroshima and Nagasaki.

Guiding Questions

How did the Allies manage to defeat Japan?

Learning Objectives

After completing this lesson, students should be able to

  • Discuss the overall Allied strategy in the Pacific from 1943–1945, and to assess how successful it was
  • Explain the reasons behind the dropping of the atomic bombs, and why the use of these weapons was controversial
  • Articulate the reasons behind the Japanese surrender, and the role the atomic bomb played in that decision
  • Identify on a map locations that were important to the war in the Pacific
  • Identify and explain the significance of the most important military engagements


While the primary Allied effort continued to be focused against Germany until the spring of 1945, public sentiment in the United States was very much in favor of doing more than remaining on the defensive in the Pacific. The crushing victory over the Japanese Navy at the battle of Midway, and the tremendous output of American industry made it possible to go on the offensive against Japan even before the end of 1942. By early 1943 the enemy had been driven from Guadalcanal, and the long slow process of overcoming the Japanese defensive perimeter began.

Allied military planners decided on a two-pronged approach to the Pacific. One drive, spearheaded by the army and led by General Douglas MacArthur, would continue through the Solomon Islands, then through New Guinea, and finally liberate the Philippines. At the same time the U.S. Navy and Marines, under the overall command of Admiral Chester Nimitz, would mount a series of amphibious operations against enemy positions in the Gilbert, Marshall, Caroline and Mariana Island chains. Eventually the two offensives would join together for an anticipated invasion of the Japanese home islands.

To carry out these offensives MacArthur and Nimitz would employ a strategy called "leap-frogging." Allied military planners reasoned that it would not be necessary to drive the Japanese from every one of their island strongholds—the key to victory would be to overcome key points in the enemy defense and seize only those islands that were most strategically valuable. By early 1944 the Americans could count on virtually unchallenged control of the skies and most of the sea-lanes, so that certain Japanese positions could be safely bypassed—their garrisons, cut off from their supply lines, would be left to "wither on the vine."

Both MacArthur and Nimitz would make steady progress in 1943 and 1944, but as time went on, Japanese troops increasingly fought to the death, so casualties on both sides were often staggeringly high. Realizing that an invasion of Japan itself would likely cause even more loss of life, President Harry S. Truman—who succeeded Roosevelt after the latter's death in April 1945—decided to use a powerful new weapon: the atomic bomb. In August two such bombs were dropped, on the cities of Hiroshima and Nagasaki. On 10 August Japan surrendered, bringing World War II at long last to a close.

Preparation Instructions

Review the lesson plan. Locate and bookmark suggested materials and links from EDSITEment-reviewed websites. Download and print out selected documents and duplicate copies as necessary for student viewing. Alternatively, excerpted versions of these documents are available as part of the downloadable PDF.

Download the blackline master for this lesson, available here as a PDF. This file contains excerpted versions of the documents used in the first and second activities, as well as questions for students to answer. Print out and make an appropriate number of copies of the handouts you plan to use in class.

Perhaps most importantly, you should become familiar with the interactive map which accompanies this lesson, and which shows the locations of important events in the Pacific theater. Clicking on these locations will bring up pop-ups that include a paragraph or two of basic information about what happened there, as well as links to pages with more in-depth coverage, plus relevant campaign maps, photographs, and/or personal accounts by those who were there.

Working with Primary Sources

If your students lack experience in dealing with primary sources, you might use one or more preliminary exercises to help them develop these skills. The Learning Page at the American Memory Project of the Library of Congress includes a set of such activities. Another useful resource is the Digital Classroom of the National Archives, which features a set of Document Analysis Worksheets. Finally, History Matters offers pages on "Making Sense of Maps" and "Making Sense of Oral History" which give helpful advice to teachers in getting their students to use such sources effectively.

Lesson Activities

Activity 1. Allied Strategy in the Pacific, 1943–1945

Using the documents and the map below, have students make a list of the areas that the Allies hoped to capture. After they have done this, they should click on locations 18–36 on the interactive map. To help ensure that students use the map to its full advantage, teachers might wish to have them complete the "scavenger hunt" that is included in the Master PDF (pages 7–9 in the PDF). Based on their examination of these resources, students should be able to discuss broadly the overall Allied strategy and why it was adopted. Further, they should be able to identify which strategic goals were met, and which were not.

Direct students to the following documents, either online or as handouts printed from the Master PDF (pages 1–6 of the PDF).

Have the students answer the following questions based on their reading:

  • What had to occur before Allied forces could concentrate solely on the Pacific Front?
  • What had to occur before an invasion of Japan could take place? Why?
  • Why was China so important to success in the war against Japan?
  • Why were lines of communication so important to military planners?
  • What were planners hoping would happen once the United States gained control of the seas?
  • What were the primary objectives of U.S. operations for 1943–44?

Next ask the students to consult the interactive map, which will demonstrate how the offensive played out in reality.

Activity 2. Truman's Decision to Drop the Atomic Bomb

Distribute to the students the set of documents in the Master PDF (pages 10–15 in the PDF) pertaining to President Truman's decision to use the atomic bomb against Hiroshima. These are excerpts from longer documents found online at the EDSITEment reviewed resource Project Whistlestop.

Based on their reading of these documents, students should then write an essay in response to the following: "Why did President Truman decide to use the atomic bomb against the Japanese city of Hiroshima?"

Activity 3. Japan's Decision to Surrender: A Debate

Print out and distribute to students the set of documents in the blackline master dealing with the decision of the Japanese government to surrender in the summer of 1945 (pages 16–23 in the PDF). These include:

From the EDSITEment reviewed resource The Avalon Project at Yale University:

From the EDSITEment-reviewed resource Project Whistlestop:

Excerpts from "Japan's Struggle to End the War," a study done as part of the U.S. Strategic Bombing Survey.

After the students have had an opportunity to read through the documents, divide the class into pairs and give them the following resolution to be debated:

“The use of the atomic bombs caused Japan to surrender.”

Have one student in each pair take the pro side of the debate, and the other take the con side. Each pair should use the worksheet for this activity (page 24 in the PDF) to conduct a silent "Yeah, but" debate. The first student should begin by citing a fact from one of the documents in support of the resolution; this should be written on the "pro" side of the worksheet. The second student then follows by citing another fact in opposition to that point. This should continue until one student or the other runs out of relevant facts.

After students have completed the debate, teachers may wish to have the class discuss this topic, bringing in what they have learned from the second activity to address the larger issue of whether or not Truman's decision to drop the bomb was wise.


After completing this lesson, students should be able to write brief (1–2 paragraph) essays answering the following questions:

  • What was the Allied strategy for defeating Japan after 1942?
  • Why did President Truman decide to use the atomic bomb? Why was this decision controversial?
  • Why did Japan surrender? How important a factor was the atomic bomb in the decision to surrender?

Students should also be able to identify the following locations on a blank map of the Pacific region, available at this site, which is accessible via the EDSITEment-reviewed resource History Matters:

  • Solomon Islands
  • Gilbert Islands
  • Marshall Islands
  • Mariana Islands
  • Iwo Jima
  • Okinawa
  • Manchuria

Finally, students should be able to identify and explain the significance of the following:

  • "leap-frogging"
  • Philippine Sea
  • Kamikaze
  • Leyte Gulf
  • "Enola Gay"
  • Atomic bomb

Extending The Lesson

Any of the engagements listed as locations on the interactive map could be topics for research papers, PowerPoint presentations, etc., as each pop-up includes a wealth of source material on the subject.

A great many movies have been made about this phase of the war in the Pacific—Sands of Iwo Jima (1949), Operation Pacific (1951), Run Silent, Run Deep (1958), In Harm's Way (1965), and Windtalkers (2002)—are just a few examples. Students could be asked to watch one of these movies and write an essay comparing it to the real events on which the film was based. Here again, the sources linked from the locations on the interactive map will be useful for background.

Selected EDSITEment Websites

The Basics

Grade Level


Time Required

3 class periods

Subject Areas
  • History and Social Studies > U.S. > The Great Depression and World War II (1929-1945)
  • History and Social Studies > Themes > War and Foreign Policy
  • Critical analysis
  • Critical thinking
  • Discussion
  • Evaluating arguments
  • Gathering, classifying and interpreting written, oral and visual information
  • Historical analysis
  • Interpretation
  • Making inferences and drawing conclusions
  • Map Skills
  • Textual analysis
  • Using primary sources
  • Vocabulary
  • Writing skills
  • John Moser, Ashland University (Ashland, OH)
  • Lori Hahn, West Branch High School (Morrisdale, PA)


Activity Worksheets
Student Resources