Because there is little empirical data available on how well young children are able to use a computer mouse, the present study examined their proficiency in clicking on small objects at various positions on the screen and their skill in moving objects over the screen, using drag-and-drop and click-move-click. The participants were 104 children from Kindergarten 2 and Grade 1. The results show that children in Kindergarten 2 clicked and moved slower than children in Grade 1. Nearly all of the children were able to click within 3 mm horizontally and 6 mm vertically from the centre of a 3 mm target. The findings also demonstrate that in educational software drag-and-drop is the most appropriate movement procedure as it was found to be faster than click-move-click and resulted in fewer interaction errors. Interesting differences between horizontal and vertical movements were found. It is concluded that young children are generally well capable of using a mouse to operate educational software, making this a suitable input device for such applications.