Choo, a 15-year-old junior at the Breddell-Westlake back home, tamed the par 72, 6,774-yard Wack Wack East course on nines of 35 and 36 and he likes the prospects.
"I enjoyed the golf course today," he told sportswriters. "And I like the prospects of not only retaining the Class A crown but also winning the overall championship."
De Villa pieced together nines of 50 and 52 for 102 to run away with the girls beginners class crown while Francisco shot 139 on 65 and 74 to also post an easy victory in the boys division, each set for 18 holes.
The Philippines J.R. Tanpico started his defense of the special division title with an 80 despite tonsillitis, but he has to share the lead with South Koreas Son Hyeon Ho.
Thailands Hinmoratanakorn Anujit came up with a 76 to pace the boys Class B. Malaysias Ng Choo Sion Daniel took second place after an 80. South Koreas Shim Jun Bo and Koh Dhengshan of Singapore were tied for third with 82s.
Mike Arroyo, the first Gentleman, and Sang Youl Eom, the Samsung Electronics Philippines Corp. president and chief executive officer, hit the ceremonial drives to officially kick off the event.
A big crowd witnessed the occasion, including Philippine Junior Golf Federation president Edgardo "Boy" Cantada, who launched the event in 1998.
Aside from Samsung as the title sponsor, other supporters are Cebu Pacific, Wilson Sports, Morelia Tours and Travel Inc., Herma Group of Companies, Pagcor.
Mitsubishi Motors, Bingo Bonanza, Toyota Otis, Pisanti Golf, Philippine Flour Mills, Rizal Rep. Gilberto Duavit, Takanobu Taira, Airlift Asia Inc., Raul Jorge, Sysu International, Absolute Distilled Water, Gatorade and EDSA Shangri-La.
Seventy six players41 foreigners and 35 localsare competing this year. The best scorer in the Classes A and B will also win the overall championship.
Choo had a good starts as he made a 25-footer to birdie the first hole. The other birds came on the fifth after a great chip, the 12th from 10 and 18 from eight.
What marred the days only subpar round were Choos bogeys on the seventh from the bunker, the 10th from over the green and the 15th after chipping poorly.
"I know full well that the East course is the home of your No. 1 tournament, the Philippine Open, and I feel great," Choo said. I hope I will feel the same the next three days."