Mass Evacuation of a Population

Setting: Self-contained mountain community, isolated. Low-level tech, lots of use of specific types of magic. Magic is rituals and enchanted items, some effects to self and surroundings.

Population: Two hundred. Specifically, a dozen elderly, twenty ranging toddler to preteen, about seventy adults, rest are teen to very early twenties. The latter are technically adults, but are junior members of the society until passing a specific event.

Situation: Several of the junior members learn of an impending attack. The adults are not complicit, but are under geas and bound from interfering the incoming force, passing information about it to the younger set, or leaving under their own power.

My issue: How in Hades do I organize a hundred teenagers as the backbone for a mass evacuation? I've already got the problem of supplies covered, but how does one go about kidnapping almost a hundred healthy adults without them figuring it out too soon? I'd rather a solution based more in the real world than one that blames magic for everything.

Help?

The geas stops them from leaving by their own will. As long as they aren't the ones to decide to leave and don't have a hand in it, the geas remains inert.

The lack of resistance is part of a larger plot. They can't do anything that actively delays or hinders the incoming force.

What I need most is a method or motivation for the adults to go along with the teens. I like the idea of the flood, and pulling that off might let me start a few other things earlier. I'll have to give that one some thought.

They can't just follow their kin-that's a decision to leave. The Head Honcho holds their geas and is the one preventing the adults from leaving. The junior citizens aren't under geas. But flooding the village- I like that more than I probably should. Thanks frimble3. I've got a couple of different ways to pull that off.

I'm reluctant to dope them. It seems too easy an out. But flooding a part of the complex and loosing a few toddlers in the chaos resulting would be an easy way to separate everyone for ambush. A determined toddler outdoors can be harder to catch than a greased piglet.

Dirtsider, the geas only makes them do one thing: obey the leader of their clan/order/what-have-you. That leader is not within this community and has ordered them to stay put and provide no resistance to the approaching force. Being junior members, the teens haven't been brought under the geas yet and can do as they like.

Not if he knew about it in advance and didn't tell anyone. The geas holder isn't a member of the approaching force, nor is the approaching force part of their order/community. It's a rather complicated bit and the evacuation is a lynchpin. They'll be taking care of the geas later, but for now, getting out of the way is more important.