Is the leader of the seder supposed to hide the afikoman so that the kids can find it, or are the kids supposed to hide it so that the leader can find it? And what is the point of this hide-and-seek game anyway?
According to the opinion cited by the Be'er Heitiv (OC 473:19), it seems that the kids are the ones to hide it, not the adult. Actually, he doesn't say anything about hiding, just that the kids take it.
ועח''י סי' תע''ב ס''ק ב' טעם למנהג שהתינוקות לוקחים האפיקומן:
And see Chovas Ya'ir(?) 472:2 for the reason for the custom that the children take the Afikoman.
I don't have access to Chovas Ya'ir (if that's even the correct interpretation of the acronym), so if someone has a copy, please let me know what he says.