This article is part of a larger project focusing upon explanatory illustrations thatchildren encounter in pre- and primary school education. The research questionsconcerned (a) how preschool children make sense of iconic symbols when placingitems of refuse on illustrations of refuse bins in a sorting task and (b) whatstumbling blocks they encounter when interpreting these symbols. Video datawere collected with 30 children between four and five years of age. From thechildren’s verbal and non-verbal interactions, four different categories of sensemakingwere constructed: by material, by object type, by appearance and byfunction. Three stumbling blocks were identified. The first had to do with givingthe symbols a different logical meaning to the intended one; the second relatedto what materials the different refuse items were made of; the third was beingable to stick to one correct way of interpreting each symbol.