Standing in front of the schoolchildren at Desu Madra Secondary School in Mohali, in the Indian state of Punjab, Satnam Singh Daun spreads his props out on the table: scarves and money that vanish, cards, powders that burst into flames, some rope, matches, vials, cotton wool. He looks like a magician about to start a show at a child's birthday party.

But the tricks are not for entertaining the children. Daun is using them to expose the godmen, gurus, astrologers, charlatans, soothsayers, palmists, charm sellers, quacks, and humbugs who are so popular in India.

The children, seated on the ground in the bright sunshine and humidity that follows a monsoon downpour, listen intently to Daun as he pours scorn on superstition. He performs the same tricks that are used by holy men to exploit the gullibility of Indians and project themselves as possessing supernatural powers - making money disappear or turning 100 rupee notes into 500 rupee notes, producing ash from nowhere, swallowing fire.

''It's because they are too stupid to become teachers, doctors or scientists that godmen become astrologers to fool people,'' Daun says.

''They want you to use amulets and trust in the stars instead of using your reason. These holy men are holy fools tricking you. Be rational, use your minds,'' says Daun, as a rooster in the school grounds crows on cue as if to say ''hear hear''.