(see the Philokalia)
A unique analogy within Orthodoxy and the writings of the Church Fathers is the idea that our mind is likened to an airport. The spiritual warfare that we, and our children, live amongst is as the numerous planes flying overhead at any given moment. These thoughts, or airplanes, can land in the mind, which is the entry point to our soul. Our task is not to allow the harmful planes to fuel up and stay parked at our airport! We must use the God-given discernment we have to dismiss the planes before they take root and darken our soul.
We do not blame ourselves strictly for the planes flying over us, for example, to say that anyone is created evil, or a bad person because of them. Rather, a person can be taken hostage to harmful ideas, which when rooted in the person, only then become their responsibility. This is what we mean when we say, a person has the capacity to sin, and fall to the passions. The passions themselves do not originate from within us. We were created good. We only live within a fallen world, and when we fall, we are offered the medicine of repentance and metanoia that only Christ's Church can offer us.
Simply put: Standing watch is being ready to tell those negative thoughts to fly away and we must teach our children to ignore them. Here's how I used this idea with a young girl.
During the Divine Liturgy one day, at the time of the holy consecration of our Lord's Body and Blood, a beautiful God-fearing young girl in our community was next to me and became quite frightened and distracted by the thought that she saw a spider. I am not certain if the spider was indeed there, but regardless, it took her and my attention away from our Lord for that brief moment.
So, I ask, was the evil one victorious in his attempt to steal our thoughts away from Christ? When explained, I believe this young girl understood. Not because of any extraordinary analogy, but because her mother has equipped her with the necessary tools for battle, and combined with the grace of God, she's prepared to struggle for the Kingdom.