As a classified substitute, you're a able to fulfill a versatile role within the organization as a temporary employee in: the classroom, administrative offices, and school district warehouses among other locations.
In these various roles, you may get a glimpse at different jobs that exist within the school district. Additionally, substitutes are encouraged to apply for any job openings within the district. Working in different roles can be beneficial for temporary workers as this allows them to get a realistic preview of the job.
I can't really speak for the overall culture for the district, but there are subcultures within each office depending on management, location, and the people that work there. As a classified sub, I've worked under great and poor managers throughout the years.