Not really. In order to be truly child freindly you need to get rid of the wasps, and any "natural"/herbal method will be using plants containing either very strong poisons (nicotine) or the same chemicals a fumigator would use (pyrethrins-they come from a kind of daisy). Many of the old remedies, such as smoking out with tobacco or boiling water, are not reliable, and can lead to counterattacks from very upset wasps.