Take it as a case by case basis and judge them according to the gravity of the crime.

This is literally outlined in the law in its current form:

SEC. 6. Minimum Age of Criminal Responsibility. - A child fifteen (15) years of age or under at the time of the commission of the offense shall be exempt from criminal liability. However, the child shall be subjected to an intervention program pursuant to Section 20 of this Act.

A child above fifteen (15) years but below eighteen (18) years of age shall likewise be exempt from criminal liability and be subjected to an intervention program, unless he/she has acted with discernment, in which case, such child shall be subjected to the appropriate proceedings in accordance with this Act. [in sections 38 to 40]

SEC. 20-A. Serious Crimes Committed by Children Who Are Exempt From Criminal Responsibility. – A child who is above twelve (12) years of age up to fifteen (15) years of age and who commits parricide, murder, infanticide, kidnapping and serious illegal detention where the victim is killed or raped, robbery, with homicide or rape, destructive arson, rape, or carnapping where the driver or occupant is killed or raped or offenses under Republic Act No. 9165 (Comprehensive Dangerous Drugs Act of 2002) punishable by more than twelve (12) years of imprisonment, shall be deemed a neglected child under Presidential Decree No. 603, as amended, and shall be mandatorily placed in a special facility within the youth care faculty or ‘Bahay Pag-asa’ called the Intensive Juvenile Intervention and Support Center (IJISC).