Children between the ages of 3 and 6 years were asked to predict their success or failure in two different tasks: a box-lifting task and a task in which marbles had to be rolled through gates of different widths. Both tasks had five difficulty levels which were presented either simultaneously or successively. Along with the verbal or nonverbal responses to questions about their chances of success, the time children needed to make the prediction (decision time), the number of eye movement during the decision time, and, in the box-lifting task, the time taken to approach the box were assessed. The results indicated that children from 3 years on make realistic assessments of their chances for success at the five different difficulty levels. The simultaneous presentation mode enables the children to make more realistic success predictions only in the marble-rolling task. For the box-lifting task, children seem to have a stabilized difficulty scale which allows sure predictions without the whole range of difficulty levels being physically presented.