Mills High School in Millbrae is home to many college-bound students. For them, passing the advanced placement test would mean being able to skip introductory college courses - a potential savings of tens of thousands of dollars.
"To me this means I won't be able to enter as a sophomore at Boston University," student Erika Lee said.
Unfortunately for these students and nearly 300 others like them, the results of the advanced placement test they took are being thrown out and the students must retake them.
Some students from Mills High School took at least two AP tests in various subjects; One even took five.
However, the educational testing service which administers such tests as the SAT and advance placement tests accused Mills High School of not following proper testing guidelines and threw out all the test results.
That punishment has the Associate School Superintendent Kirk Black perplexed.
"To invalidate all those tests without a thorough investigation, each and every test seems to me to be a little rushed," Black said.
The ETS says among the guidelines potentially violated were that students were sitting too close together.
There may have been too many students sitting at one desk or table. The desks were too close together. And the desks were not all facing in the same direction as required.
ETS told ABC7 News Mills High School was responsible for following the proper guidelines.
Seven On Your Side's Michael Finney asked the San Mateo High School District how so many violations could have occurred on such a massive scale.
"I don't agree with the premise of your question. How did it happen on a massive scale? I don't know. The investigation I don't think is adequate enough to conclude anything was done on a massive scale," Black said.
The students are being given the option of taking their tests over in the second week of August. For them, that is not an option.
"Other students are out of the country and it is summer vacation and they are not in the country. How are they supposed to take the retakes," Vasser College student Raymond Magsaysay said.
These students have reached out to Rep. Jackie Speier and State Sen. Leland Yee.
"At this point in time, we're looking into the matter and we're hoping to find a way we can help the effected students," District Rep. for State Sen. Leland Yee Kevin Fong said.
Meanwhile, the students are being forced to restudy for tests they don't think they should have to retake.
"And for people who took more than one subject, you have to prepare for four or five tests to retake it. We don't have any more materials. We forgot all that stuff. We prepared for that over our senior year. And we probably did well on it and now we won't ever know our scores because they were invalidated," Arizona State University student Natalie Tarangioli said.
In all, more than 625 tests will have to be retaken. A meeting will be held at Mills High School at 7 p.m. on both Monday and Wednesday in the school library to update parents and students on the situation.