In the candle problem (Duncker, 1945), subjects must attach a candle to a vertical surface, using only a box of tacks and a book of matches. Subjects exhibit functional fixedness by failing, or being slow, to make use of one object (the tack box) as a support, rather than as a container, in their solutions. This failure to produce alternate functions is measured against improved performance when the tack box is presented empty rather than full of tacks (i.e., not preutilized as a container). Using an analogous task, we show that functional fixedness can be demonstrated in older children (6- and 7-year-olds); they are significantly slower to use a box as a support when its containment function has been demonstrated than when it has not. However, younger children (5-year-olds) are immune to this effect, showing no advantage when the standard function is not demonstrated. Moreover, their performance under conditions of preutilization is better than that of both older groups. These results are interpreted in terms of children's developing intuitions about function and the effects of past experience on problem solving.