# What happened A webinar hosted by Education Week featured Gwinnett County Public Schools and Frontline Education describing a data-driven approach to substitute hiring, retention, and fill-rate management. Gwinnett's substitute team publishes monthly fill rates for every school and uses those numbers to make hiring and operational choices.
# Why it matters
# The Gwinnett baseline
- Active substitutes: 4,400
- Percent of those active who worked during the period: 94.5%
- Overall fill rate (last year): just under 90%
- No individual school had a fill rate below 70%
These measures gave Gwinnett confidence to tighten hiring standards and focus on retention and placement rather than simply adding bodies.
# How they changed hiring Gwinnett rebuilt its substitute hiring process to prioritize fit and reliability over volume. The district used the school-by-school fill-rate data to decide where it could hire fewer substitutes and where it needed to recruit more. That allowed them to be more selective about who entered the substitute pool while maintaining system coverage.
# How they use fill-rate data Monthly fill-rate reports go to the district board and guide operational responses. The data reveals which schools struggle to get coverage and which ones consistently achieve high fill rates. With that visibility, the district can:
- Concentrate recruiting for specific schools or school clusters.
- Adjust outreach and onboarding processes to meet localized needs.
- Monitor the effect of changes over time and report progress to stakeholders.
# What keeps substitutes coming back The webinar outlined attention to common retention levers (described by Gwinnett's HR leader) rather than offering a single solution. The district focuses on practical, building-level factors that influence a substitute's decision to accept and repeat assignments. These include predictable scheduling, clear communication about duties, and supports inside the school that make a substitute's day manageable.
# What drives substitutes away
# Control points for administrators Gwinnett's message: more of your fill-rate outcome is within your control than many administrators assume. Tracking school-by-school performance enables targeted interventions, such as concentrating reliable substitutes in high-need schools, improving onboarding, or changing assignment practices that cause substitutions to be declined.
# Speakers and perspectives
- Velia Verdiguel, Senior Human Resources Manager, Substitute Management Development, Gwinnett County Public Schools. She oversees recruitment, onboarding, and professional development for substitute employees and led Gwinnett's hiring redesign.
- Kevin Agnello, PhD, Group Product Manager, Frontline Education. He focuses on product strategy for human-capital analytics and connecting HR system data to operational decisions.
# Practical next steps for districts
- Begin monthly, school-level fill-rate tracking if you don't already.
- Compare active-substitute counts to percent who actually worked to assess pool effectiveness.
- Use fill-rate data to target recruiting and to justify raising hiring standards where coverage is stable.
- Audit building-level substitute experiences (scheduling, communication, supports) to identify retention friction.
# Takeaway