Complex sentence: The school houses members from the Boy Scouts of the Philippines (BSP) and Girl Scouts of the Philippines (GSP) as an extra curricular activity and again from fourth grade up to junior year.
Split into simpler sentences: The school houses members from the Boy Scouts of the Philippines (BSP) and Girl Scouts of the Philippines (GSP). Scouting serves as an extra curricular activity and from fourth grade up to junior year.