Arguably, the variables that affect educational planning include, but are not limited to: 

• Funding and budgeting

This includes all the money allotted toward salary, infrastructure, purchases, benefits, maintenance, and every other expenditure for a specific period of time. This period of time is called a fiscal year. By definition, a fiscal year is the length of time that a budget is supposed to last for an educational year.

• The human factor  

Outsourcing and in-sourcing workers means finding enough people to man the different needs-based services that either provide the education, protect the premises, or maintain the grounds. Think of the amount of teachers needed to educate. Add to that the slots for the people who will support the mission of the organization by providing the teachers with what they need. Then, think about the other stakeholders in the community at large. All of these factors are equally important in the long run. 

• Laws

There are such things as educational laws that protect both students and educators. As such, legal protection is also an expenditure to think about. Laws also dictate work hours, hourly wages, licensing and workman's compensation among many other things. 

• School Board regulations

While educators meet and plan for curriculum and standards, the school board acts as a major political force that curbs, moderates and votes in favor or against changes made to the educational system. In some states the school board has as much power as to fire and hire superintendents and principals. Some school boards have the power to forbid the teaching of some things over others. As they are members of the community voted in by other board members, there are allegiances and circles of trust that directly affect educational planning. 

• The community

The community must be taken into consideration as far as the services it will need, the type of infrastructure it can support, the resources that can be found, and the demographics of the clients. A high-risk community cannot support or be educated by an institution that cannot meet its immediate needs. This in no way implies that high-risk communities (where there is high crime and minimal parental support) cannot be rehabilitated through education. It CAN. However, to get to a point of total change, small steps of immediate importance must be met. These include safety and security, meeting nutritional needs, addressing special populations, language services, and much more. 

Follow UNESCO and you will find a lot of publications (I include one of Coombs with the answer). You will find that there are indeed many variables that ease (and/or complicate) educational planning.