Everything you need to understand or teach Sacred Ground by Mercedes Lackey.
Sacred Ground's primary theme is the timeless one that evil motives and acts produce more evil, which must be stopped for the world to be set right again. This idea is worked out on both the mundane and the supernatural planes. Rod Calligan's greed leads him to build on an environmentally disastrous site. When his project falls apart he raids Indian graves and plants explosives. He plans to blame Native American activists for the damage and to collect insurance to recoup his losses. This leads to several deaths and to more violence as he tries to cover up his deeds.
But in raiding the graves he also disturbs the spirit of Watches-OverThe-Land, a great Medicine Chief of the last century. This brings onto the present scene the struggle of the Medicine Chief with his ancient, malevolent adversary, along with a flock of minor vengeful spirits called Little People...