The alleged scheme involved helping students cheat on entrance exams, as well as getting non-athletic students admitted on fake athletic scholarships.
Elite schools Yale, Stanford and Georgetown were among the destination universities.
There was no suggestion that the schools were involved in wrongdoing.
Who was a part of the alleged scam?
The defendants are largely wealthy and also include CEOs of major companies.
“These parents are a catalogue of wealth and privilege,” said US Attorney Andrew Lelling at a news conference about the investigation known as Operation Varsity Blues on Tuesday.
According to the charging documents, Ms Huffman made a “charitable contribution” of $15,000 (£11,500) to participate in the scheme on behalf of her eldest daughter.
She allegedly arranged to use the scheme a second time, for her younger daughter, before deciding not to do so.
Ms Huffman was charged with conspiracy to commit mail fraud and honest services mail fraud. She was secretly recorded discussing the scheme with a co-operating witness.
What’s the reaction?
USC said it had fired two employees who were indicted in the alleged bribery case: senior associate athletic director Donna Heinel and water polo coach Jovan Vavic.
Court documents say Mr Vavic placed two students on his water polo team to help them get into the university, and was paid $250,000.
Ms Heinel also allegedly accepted bribes to facilitate admissions.
“USC is in the process of identifying any funds received by the university in connection with this alleged scheme. Additionally, the university is reviewing its admissions processes broadly to ensure that such actions do not occur going forward.”
Georgetown, Yale, UCLA, Wake Forest and the University of Texas released similar statements acknowledging the investigation.
On social media, many have expressed outrage over the alleged scam, pointing out that the US college system is already biased in favour of wealthier, white Americans.
And others have noted that for the mega-rich, it’s easy to legally donate money to a school in order to receive admission.