American reporters and news media are praising a group of high school students from southeastern Kansas.
The students attend classes at Pittsburg High School and work for its newspaper.
The school has about 900 students.
Amy Robertson was named Pittsburg High's new principal in early March. School officials said she lived in Dubai. They said she would move to Kansas and start her new job before the next school year.
Robertson said she works as an education consultant in the United Arab Emirates.
After reading a press release from the school and speaking with her on Skype for a newspaper story, the high school students had some questions.
One of the students, Connor Balthazor, told The Washington Post that there were some things about Robertson "that just didn't quite add up."
He and others from the school newspaper decided to look at Robertson's credentials.
The number-one thing they found is that Robertson claimed to have high-level degrees from Corllins University in California. When they went to the Corllins' website, it did not have the look of the website of a serious university.
The site had spelling mistakes and no information about how to become a student there or which classes are required to complete a study program. It also lacked information about a university library or how much money students have to pay for their education.
The high school students worked on the story about Robertson for three weeks, and published their findings on March 31.
The students said they had found "inconsistencies in Robertson's credentials" and raised their concerns to the school district. The Pittsburg Community Schools' superintendent asked the students to continue their investigation.
The newspaper said it could not find evidence that Corllins University ever held classes in California.
And Robertson's problems did not end there. The students had further questions about her work at universities in both the United States and Britain.
On Tuesday, the school district announced that Robertson resigned.
Trina Paul is an editor of the student newspaper. She told the Kansas City Star "we wanted be assured that she was qualified and had the proper credentials."
Separately, Robertson told The Star that the students' concerns "are not based on facts."
Pittsburg Community Schools plans to reopen the position for the high school's principal.
When the news of the students' investigation came out, journalists and organizations that critique U.S. media expressed their admiration.
Todd Wallack works for an investigative team at The Boston Globe newspaper. The team was recognized in the film that won the Best Picture Oscar at the 2016 Academy Awards.
Wallack tweeted to the students, writing: "great investigative work."
I'm Dan Friedell.