U.S. Park Ranger Betsy Keene, curator of National Parks of Western Pennsylvania, explains a slide showing a damaged part of United Flight 93 during an educators seminar at the Flight 93 National Memorial in Shanksville, Pa., Tuesday, June 23, 2026. (AP Photo/Gene J. Puskar)

U.S. Park Ranger Claire Affinito, left, leads a tour for a group of educators at the Flight 93 National Memorial in Shanksville, Pa., Tuesday, June 23, 2026. (AP Photo/Gene J. Puskar)

U.S. Park Ranger Adam Shaffer, center, leads a tour for a group of educators at the Flight 93 National Memorial in Shanksville, Pa., Tuesday, June 23, 2026. (AP Photo/Gene J. Puskar)

Social Studies teacher John Boston Bradley, who teaches at Bishop McCort High School in Johnstown, Pa., pauses at the Wall of Names during an educators seminar at the Flight 93 National Memorial in Shanksville, Pa., Tuesday, June 23, 2026. (AP Photo/Gene J. Puskar)