The 18-year-old student bested 11,000 young learners from 178 countries to bag the plum, earning over PHP20 million worth of prizes.
The popular vote contest occurred at the Breakthrough Facebook page from October 23 to November 2 this year with the most number of votes entering the final round.
For Hillary, her perseverance and ambition made her win the competition designed to inspire creative thinking about the fundamental concepts in life sciences, physics and mathematics.
The Philippine News Agency sat down with Hillary to talk about her journey to winning the contest that aims to inspire youth and help the masses appreciate science.
Andales is not new to the competition as she joined the contest last year and placed third. "Two have tied as the grand winner," she said.
She did not win anything for placing third but organizers appreciated her entry and decided to give her a consolation prize of USD100,000 worth of laboratory for her school, the PSHS-Eastern Visayas Campus. The school, meanwhile, gave her a cash incentive of PHP50,000.
"I was determined to try again," Andales said, confident that she did a good performance in 2016. Hillary admitted that she spent almost a year thinking about her next video entry and as preparation, she said she watched a lot of videos on YouTube to get ideas.
For 2017, Hillary explained in a three-minute video entry the scientific concept of Relativity and Equivalence of Reference Frames understandable to the layman.
She explained, "We could compare it to two individuals' observation or opposite perceptions. For example, the numbers 6 and 9. One could see it as number 6 while the other person could see it as number 9. Nobody could actually tell if that is really 6 or 9."
"That means, even if two individuals have different perceptions, both of them could be correct," Hillary said, as she tried to simplify what the theory of relativity is about. According to her, she got the inspiration for making this video concept from watching lots of videos on YouTube.
The young lady said she became more confident and felt that she could win this time because she already knows her weaknesses and how she could improve the delivery and animation in her entree.
"I became more confident, but I did not expect to win," she said.
Last December 3, Hillary was announced as the winner of the Breakthrough Junior Challenge in an awarding ceremony held at the National Aeronautics and Space Administration's Ames Research Center in California.
As for the prize, Hillary would receive USD250,000 college scholarship, while her school would receive USD100,000 worth of laboratory assistance. Her teacher was given USD50,000 prize.
While there is no cash incentive for her this year, her mom Imelda told PNA that a lot of doors have opened after Hillary won the contest.
"There are offers from billionaires, high-level scientists for mentorship and collaboration. There are job offers as well," Imelda said.
Hillary said she wants to take advantage of her win to make education more accessible to young people by making them appreciate Science better.
She said Science is for everyone, and that "it makes everything interesting."
Hillary said she believes the youth and her schoolmates are smart and competitive. Her advice to fellow youth? To be ambitious and reach for their dreams. "You have unique characteristics. Set your dreams and standards very high," she said.
The young student said she dreams of becoming a physicist. When she was 5-10 years old, she wanted to become an astronomer. Her interest in physics grew as she wanted to do more research on cosmology, galaxy, and the universe.