Southern Isabela Academy (SIA)

At the same time that Charles Selby was collaborating with church leaders in Santo Tomas, Isabela, to establish a new high school, Northern Isabela Academy, officials from a remote community further south, in San Guillermo, Isabela, offered to donate land for another high school, provided it could be built that same year. After prayerful consideration, Charles accepted this challenging opportunity. As he later remarked, “We didn’t have enough money to start one high school in 1967… so we started two.”

Once again, Charles arranged plans for a U-shaped building with three units, to be constructed sequentially. Trusting God’s provision as he had with previous ministry buildings, Charles initiated construction by faith. He hired teams to lay the foundation, and remarkably, donations and supplies arrived exactly as needed for each stage. By God’s grace, SIA opened its doors to students in 1967, simultaneously with NIA.

In the years since opening day, SIA has produced over 4,600 graduates, and more than 3,850 students have accepted Jesus Christ as Lord and Savior and have been baptized. The school’s evangelistic efforts have significantly impacted students’ families and friends, leading many to Christ and resulting in the establishment of 12 new churches in the surrounding area.

Over 50 SIA graduates have attended or graduated from Bible colleges, serving in full-time or part-time preaching and teaching ministries. Numerous other graduates have become influential leaders within their churches, communities, businesses, professions, and various areas of society. Wherever they live, these graduates have strengthened local churches with members and leaders grounded firmly in biblical truths.

Prayer Requests

We believe in the power of prayer and invite believers to pray for each of our ministries.

Below you will find the current prayer request as provided by the leaders of this ministry!


  • Pray for renewed passion, strength, and commitment among teachers and staff as they prepare diligently for the coming school year ahead.
  • Pray for God's protection, good health, and safety for all students, teachers, and families throughout the summer break and travel.
  • Pray that the summer vacation will be fruitful for students, teachers, and families, renewing hearts and preparing them for a fresh start.
  • Pray for God's guidance, wisdom, and provision for leaders as they prayerfully plan and prepare for the upcoming school year.
  • Pray for a bountiful number of enrollees for the 2026-2027 school year, that many students will be reached and discipled.

Academic Year Highlights

2025-2026

  • 724 students were enrolled, with 271 in grades 11-12, and 357 in grades 7-10, and 96 in grades k-6.
  • 121 students graduated from high school in March.
  • 67 students came to know Jesus Christ as Lord and Savior and were baptized.

2024-2025

  • 631 students were enrolled, with 217 in grades 11-12, and 326 in grades 7-10, and 88 in grades k-6.
  • 89 students graduated from high school in March.
  • 43 students came to know Jesus Christ as Lord and Savior and were baptized.

2023-2024

  • 642 students were enrolled, with 223 in grades 11-12, and 327 in grades 7-10, and 92 in grades k-6.
  • 108 students graduated from high school in March.
  • 69 students came to know Jesus Christ as Lord and Savior and were baptized.
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