The 3rd Community Activity- Schools
Realistically you're not going to save everyone. Some people are wired to be mentally, spiritually, and physically tough, however that manifests. People who can balance out those characteristics tend to be people who enjoy learning and educating people.
If you're a spiritual person, and not an angry fundamentalist, then the love of the Source tends to include a love of people. You might have ideas along a long continuum about conversion of people to your branch of spirituality, but by and large, most missionaries build schools and hospitals as well as places to worship.
Some people will survive based on becoming a keystone species in the food chain. The keystone species is the predator that sits at the top and feeds off the rest of the ecosystem. They might or might not have to move based upon the carrying capacity of the environment and season. Those kind of folks tend to self-destruct based upon history i.e. the Mongols during the medieval period, but still for a time they can be a major concern.
Since food resources will be low, expect that some people will starve, either by non-cooperation, lack of preparation, lack of balanced characteristics, disease, etc. Since people tend to ration food, expect weakness. This tends to work hand in hand with predation. Since people realize they will get weaker, if people are sociopathic, then they will attack based upon their time of being strong and to replenish supplies before others consume them. This means that you also must be realistic about home and community defense. If you are safe, but your next door neighbor isn't, and they're a great gardener, doctor, teacher, spiritual leader, herbalist, etc, then it is in your best interest to help them survive too.
Likewise, if a community brings in a good harvest, and has food stores and supplies in abundance, then probes should be expected to determine the level of vigilance, the number of specialists (soldiers and those who can be them), and the amount of plenty to be harvested from them. Probes will come before an attack. However unless security and training is there, the probes will not be detected. Since it takes resources and soldiers to mount a probe, a predatory leader will have to make a good analysis based upon the success of a thieving mission and wasting time. If the probe members are caught, and they don't return, expect reinforcements. It meant that your community had enough and were strong enough(an abundance of calories) to mount an attack, and hence a potential target, if only to be a threat to the predator group.
The first groups to be attacked will come early when the predators are strong but attacking the weakest and most vulnerable since it means a higher likelihood of success.
The military is not organized as a series of lone wolf warriors. That would be an epic fail. The way that it works is a chain of command: an education that perpetuates more soldiers all doing certain things, behavior, and duties.
This means that education is key, both to instill the core values and some of the beliefs of the community. It also means that research is a part since that might reveal ways to replicate what another community is successfully doing. The education will be both practical lore and helping to perpetuate a command structure plus instilling a desire for independent study.
In the absence of normal routine due to the SHTF, a school will be vital to easily transmit education to adults and children on ways to cope. They'll learn practical survival skills first, then move up Maslow's Hierarchy of Need to self-actualization. Lots of dreamers are not needed, only tolerated. Lot's of people willing to gather the best firewood that burns the most BTUs, construct traps, grow vegetables and herbs, hunt efficiently, heal the sick, artisans, and toolmakers, etc are far more essential.
Everyone will be doing more drudgery than normal. This means that children who normally would be at school and cared for will need supervision and education. Likewise the adults of the community will need to learn how to do things in the most efficient and pleasant manner in order to maintain order and continuity and security. That means that someone who is good at teaching and someone who has practical knowledge will both be necessary and welcome. A better candidate not only has those qualities, but is also passionate about it. The ideal teacher also loves their students and will fight fiercely to defend them from whatever threat there is.
Allowing and encouraging the members of the community to live in the wilderness for several days will force them to collectively use all of their abilities and lore to awaken them. They will realize the importance of what has been transmitted to them. Otherwise they will not understand its usefulness. It's a crucial Milestone. They have graduated one level. No one will ever completely graduate, but most will accomplish major milestones.
Having a central place to teach won't come for a long time and then only based upon assigning those resources. Likewise, a full-time teacher will only emerge over time. Many villages went without one for a great period of time, but few grew beyond a certain capacity without one. Since a teacher is fulfilling a role over a long period of time, and cannot collect the necessary items to completion, they must be compensated in some way. Most likely, you'll have interim teachers who either guest teach a topic, or work in tandem, or will have to settle for someone.
The rule in ministry is to take no volunteers, but recruit...recruit...recruit. Some people volunteer because they would like to be able to do something. Because people are generally busy, they are only too glad for someone to volunteer. For the role of teacher, that isn't the best strategy. Volunteers might be able to guest teach, or help, and might become a teacher over time. It is a great honor bestowed upon that person. Oblation is meaning that you sacrificed your life to the Source to be the hands of the Source.
Locating a school close to a food and water supply will be helpful. Obviously young people will need certain resources else they'll have to bring them. Some of the best education will work with combining multiple subjects in an environmental milieu. For example, having the children do an assessment of the plants in a particular area, making a map, counting up the species, studying the biology and chemistry, and writing or doing an oral report shows command of that knowledge. It's the drudgery of rote learning in a classroom that bores them. Making pottery, or flutes, or skinning a deer hide and sewing it, are all ways or transmitting lore that helps the community and adds beauty and value and happiness. Tracking an animal by examining fecal remains, tracks, rubbings, fur remnants, being quiet and observant, are all excellent ways of feeding the community and providing necessary tools and leather. Taking a class through a forest silently and then stopping and making them recall how many plants they saw, smelled, tasted, heard, felt will make the totality of their senses open. That is enlightenment.
Anyone who learns in this manner about the Earth versus thinking food comes from a jar, or that eggs comes from the grocery store, will no longer act in the same way to devalue Life and the interconnectedness of all things.