Sy knocked down 867 pinfalls to defeat Sacred Heart School-Jesuit, who only had an 824 output.
Jake Yap, also from SHS-J, ended third with 765 pinfalls.
In class B, Ibale Center for Academe's Genie Silva came out as champion with 732 pinfalls.
Silva won by a 26-point margin from his closest pursuer, Chantelle Foyle of Marie Ernestine School.
Advanced Institute of Technology's Jansen Astudillo was third with 706 pinfalls.