This is a pretty standard anime but I liked it anyway. There's a school you see, there's almost always a school. The rule is no one is to be at the school after sun down. There's good reason. Under the school is a source of huge spiritual energy. Any bad spirit that gets on the school ground can use that energy to grow really strong. Luckily there are a pair of Kekkaishi (that I assume is translated as "demon buttkickers") to take care of the problem. They come from different families so they are something of friendly rivals. Of course outside forces forces them to fight together.
I like that the series flits from their childhood to the present. It gives both a bit more character than in most animes of this type. I also like their range of powers. Each is armed with spirit dog thing that can sniff out evil. Also they have the same spells. They can create a square force field. They can destroy any spirit in the forcefield and then send that energy to the afterworld. I like their creative uses of a square forcefield. Overall this is just a fun little show.