The purpose of the expedition was both scientific (creating maps and documenting plants and animals) and commercial (establishing trade and identifying natural resources). They were helped by a female Shoshone guide called Sacajawea. The Lewis and Clark Expedition traveled along the Missouri River from St. Louis to the mouth of the Columbia River. The Lewis and Clark Expedition started on May 21, 1804 and ended on September 23, 1806.

Members of the Lewis and Clark Expedition
The Lewis and Clark Expedition consisted of Captain Meriwether Lewis, Second Lieutenant William Clark, Clark’s slave York, the soldiers of the Corps of Discovery and two interpreters. The interpreters were a French Canadian called Toussaint Charbonneau, and his Shoshone wife, Sacagawea and their young son Jean Baptiste (nicknamed Pomp).

Members of the Lewis and Clark Expedition - Sacagawea
Sacagawea proved to be a brave and skilled guide. There were some reservations about taking a woman on the expedition but this was a calculated risk as her presence would assured other Native American tribes  that the expedition was not a war party - no war parties ever took women with them.

Lewis and Clark Expedition: The Goals and Purpose of the Lewis and Clark Expedition
What were the goals and the purpose of the Lewis and Clark Expedition? The purpose, aims and goals of the Lewis and Clark Expedition and the Corps of Discovery were both scientific and commercial. The goals and purpose of the Lewis and Clark Expedition was to:

• Explore the lands obtained in the Louisiana Purchase

• To study and document plants, animals, birds, geology and the geography of the lands

• Study the climate and weather

• To keep journals of the expedition

• To map the lands covered by the Lewis and Clark Expedition

• To identify the natural resources of the lands

• Establish trade and U.S. sovereignty over the Native American Tribes along the Missouri River

• Establish a claim by the United States to the Pacific Northwest and Oregon territory (refer to the 1846 Oregon Treaty)

Facts about the Lewis and Clark Expedition for kids
Facts about the Lewis and Clark Expedition are as follows:

Who was Lewis? Captain Meriwether Lewis was a frontiersman and the personal secretary of President Jefferson

Who was Clark? Second Lieutenant William Clark was a draftsman and frontiersman had once had been Jefferson's commanding officer in the army

What was the Corps of Discovery? The Corps of Discovery was a special military unit consisting of select group of 33 volunteers chosen to join the Lewis and Clark Expedition and the Shoshone guide, Sacajawea.

The Corps of Discovery was commissioned by President Thomas Jefferson

How many men were in the Lewis and Clark Expedition? 35, including Lewis and Clark

How many men died on the Lewis and Clark Expedition? Only one man died, Sergeant Charles Floyd, of acute appendicitis

When did the Lewis and Clark Expedition start? Training commenced 1803-1804. The expedition started in May 21, 1804

When did the Lewis and Clark Expedition end? The expedition ended on September 23, 1806

How long was the Lewis and Clark Expedition? 2 years 4 months and 10 days

How much did the Lewis and Clark Expedition cost? Congress approved $2,500 for expenses. The final cost for the expedition totaled $38,000

Where did the Lewis and Clark Expedition start and end? The expedition left Camp Dubois, near St. Louis, on May 14, 1804 and arrived at the Pacific Ocean in early November of 1805. They returned to St. Louis on September 23, 1806

What transport did they use? A 10-ton 55ft keelboat and two pirogues (dugout boats). They also used canoes

Were there any fights with Native Indians? Yes, a small skirmish with the Blackfeet tribe

A Newfoundland dog named Seaman accompanied the expedition

What scientific instruments were used by the Lewis and Clark Expedition? Octants, Sextants, Chronometers, Compasses, Surveying instruments. They also used Nautical almanacs

What were the ages of the men on the Lewis and Clark Expedition? The youngest man (George Shannon) was 17 years old and the oldest (John Shields) was 35 years old. The average age of all the men was 27 years old.

What problems were encountered by the Lewis and Clark Expedition? Crossing the Rocky Mountains, rapids, bear, snakes, mosquitoes and cold weather

When did Lewis and Clark reach the Pacific Ocean? November 7, 1805

How many miles did the journey cover? 8,000 miles

Congress established the 3,700-mile (6,000-km) Lewis and Clark National Historic Trail in 1978.

Results of the Lewis and Clark Expedition
The results of the Lewis and Clark Expedition included the following:

• More than 140 maps of the region were produced by the Lewis and Clark Expedition

• 178 plants that were new to science were identified

• A catalog of 122 animals were made

• Samples of minerals, rocks, fossils and natural resources were brought back

• Established relations with the Native American Indians

• The culture of the Native American Indians would decline

• The Lewis and Clark Expedition fired the imagination of America and led the way west

Lewis and Clark Expedition for kids: The Corps of Discovery
The Lewis and Clark Expedition consisted of special volunteers who had the skills to undertake the long expedition of discovery. The journey was dangerous, the expedition would explore unknown lands and be confronted with both friendly and hostile Native American Indians. The men chosen for the Corps of Discovery were all unmarried. They were fit and healthy possessing the skills necessary to undertake such a long expedition of discovery.

The Corps of Discovery was a military unit whose members were excellent hunters, skilled in the use of weapons and many had fought in the Indian Wars. Their knowledge included botany, astronomy, cartography and (map making). Others had artistic abilities to draw pictures of the plants and animals. The Corps of Discovery were well trained and extremely equipped with the most advanced weapons of the day and excellent cartography equipment.

The members of the Lewis and Clark Expedition were also equipped with tokens of peace to present to the Native Americans such as medicine and trinkets. The also took special Indian Peace Medals, minted in silver displaying a portrait of President Jefferson to distribute to Native American tribes with a message of friendship and peace.