Tan shot one-under-par 28 on the first nine then went home with an even-par 27 on the back nine to log 55 points and pace class A of the boys' division.
At second spot is Korean Jae Yang with 51 points while Cebuano Franz Ian Dy is at third with 48 points. Adrian Woo and Leonad Lofranco are a point further back with 46 apiece.
Pacing class B is Chepe Dulay of Negros with even-par 54 strokes on nines of 26 and 28.
Cebuano Big Jan Ybañez is at second with 46 points followed by Franz Olea also of Cebu with 38.
VJ Vasandani and Lee Gyeong Jun share the lead of class C, but an exciting battle looms in this category as Cebuano Angelo Jose Gandiongco and Clyde Mondilla are just two points behind with 44 points apiece.
Martin Mendoza shot 41 points and Algene Figuracion is three points back with 38.
Bukidnon's Ram-ram Roque heads the field for class D with 40 points and is followed by Martin Manghrablian with 36 and Gelbert Gamolo with 31.
Jason Villarosa leads class E, which played only nine holes shooting 13 points while Carl Chabon is at second with 12.
Bayani Garcia, the lone bet in the special division, shot 46 points. GIRLS' DIVISION
Cebu's Hannah Wong scored 37 points and is going solo in class A.
Cebuana Irina Gabasa set the pace for class B with 46 points on nines of 24 and 22. Behind her is Cebuana Stephanie Olea with 40 and two strokes behind is Kristine Leonen with 38.
Juily Vasandani paces class C with 36 points followed by Kim Sung Hoon with 29 and Emmylou Tan with 22.
In class D, Sunny Chung leads with 40 points followed by Kim Min-Ji with 35 and Yang Ha Ryung with 32.
In class E, Shailesh Vasandani and Pamela Mariano are tied on top of the field with 23 points apiece. Also tied for second are Joan Hortillano and Rainstar Roque with 20 points each.