Here's another half dollar from the classic era (1892-1954) of US commemorative coins - the 1926 Oregon Trail Memorial half dollar.
The coin was struck "in commemoration of the heroism of the fathers and mothers who traversed the Oregon Trail to the Far West with great hardship, daring, and loss of life, which not only resulted in adding new States to the Union but earned a well-deserved and imperishable fame for the pioneers; to honor the twenty thousand dead that lie buried in unknown graves along two thousand miles of that great highway of history; to rescue the various important points along the old trail from oblivion; and to commemorate by suitable monuments, memorial or otherwise, the tragic events associated with that emigration-erecting them either along the trail itself or elsewhere, in localities appropriate for the purpose, including the city of Washington."
(From the coin's authorizing legislation.) The coin was struck in multiple years (but not all) between 1926 and 1939.
Five stars are seen on the coin's obverse (though most collectors refer to it as the reverse), under the Conestoga wagon and the inscription "Oregon Trail Memorial." The US Mint's official description of the coin does not list a meaning for the stars, so they are often either just given a passing reference or not mentioned at all by authors when they describe the design.
I believe they are a reference to the five states/territories that Ezra Meeker traveled through on his journey over the Trail in 1852; Meeker started in Indiana, crossed Illinois, then Iowa and then traveled on through the Nebraska Territory before ending his journey in the Oregon Territory - five jurisdictions in total. Meeker was the President of the Oregon Trail Memorial Association and was the primary catalyst behind the Association's efforts to mark the trail and to get the coin approved to help raise the funds needed to carry out the mission.
1926 Oregon Trail Memorial Association Half Dollar

I've posted multiple time about the Oregon Trail Half Dollar, you can find the posts here:
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