In some tasks, children show improved performance when allowed to make choices about task features. We conducted two experiments to examine the nature of this effect on 4-year-olds’ cognitive flexibility. Children completed one of two conditions of the dimensional change card sort (DCCS), wherein children are asked to sort items by one dimension (e.g., shape), and then to switch and sort by another (e.g., color). In the standard condition, children were instructed to switch and sort by the second dimension after 6 pre-switch trials. In the choice condition, children were additionally allowed to make a choice before the rule switch (e.g., to touch either a sun or a moon icon). Children’s post-switch performance was significantly higher in the choice condition than in the instructed condition, indicating that giving children choice can aid their cognitive flexibility, even if this choice is not task relevant.