They're following suit behind other Ivy League schools such as Harvard, Yale and Dartmouth.
"The pendulum has swung all the way in the other direction, and the narrative once again is, doggonit, I guess we need those tests," Adam Ingersoll, co-founder of Compass Education Group said.
Ingersoll is a co-founder of Compass Education, a national provider for test prep and academic tutoring.
He says the school first went test-optional in 2020 because public health concerns during the COVID-19 pandemic.
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The university said in a statement on Friday, "The renewed testing requirement will allow Stanford to consider the fullest array of information in support of each student's application."
They add a review of their policy also found test scores are an important predictor of academic performance at Stanford.
"They're simply saying that we think more information is better, and we want to be trusted to consider everything that is available about a student's academic preparedness," Ingersoll said.
Though many students say that explanation isn't good enough.
"I feel like they need to say why because if you have data that suggests, like if you're mad because you think the quality of students is getting worse, then like you can say that and say why you think that," Alan Deloera, A Stanford senior said.
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Deloera is a first-generation college student coming from a low-income family.
He was part of Stanford's first class of students that weren't required to submit test scores.
"I myself was a test-optional student, and I've had plenty of success here at Stanford so I think that you don't really need to do good on that test to be able to do good in school," he said.
Carmen Davalos was part of the last class of students required to submit test scores.
"I don't see that there's this huge like need for it given that the classes that have been here afterwards with no requirement are clearly very capable, very smart," Davalos said.
Still, he doesn't think it's fair to add the requirement back in.
"I'm pretty confused about it to be honest because I have heard a lot of like the criticism that ACT and SAT act as a further barrier of entry for certain populations like people of color," he said.
Stanford says this applies to all students currently finishing 10th grade and going into 11th grade in the fall.
They will continue to be test-optional for the future class of 2029 applying this fall.