There has always been some debate on whether drag and-drop is too difficult to use for children because they may not be able to hold the mouse button pressed while moving the mouse. We researched and compared two articles: Drag-and-Drop vs. Point-and-Click Mouse Interaction for Children by Kori Inkpen, Kellogg S. Booth and Maria Klawe (1996) and Drag-and-drop errors in young children’s use of the mouse by Afke Donker and Pieter Reitsma (2006).
The older article, proved that the point-and-click method was preferred by students, (68 children, of age 9-13) more so by girls than boys who had a larger error rate in dragging and dropping. 53% of the children said that the point-and-click was easier, and 37% complained that the drag-and-drop made their finger or hand tired. 47% of the children that preferred the drag-and-drop said it was because they were more familiar with the interaction. Some children mentioned that they preferred drag-and-drop because it gave them more tactile feedback. (This ties in with Buxton’s view  that that a kinesthetic connectivity can help to reinforce the conceptual connectivity of the task. Unfortunately there is no research to date that might prove if the benefits from conceptual feedback outweighs the physical difficulty of performing the drag-and-drop.) There was a significant difference between girls and boys feedback, which today might be reduced with girls playing video games almost as much as boys do.
The newer research was conducted with 53 children in Kindergarten, mean age of about 5, and 50 children in Grade 1, of age 6. This research proved that most of the drag-and-drop errors made were not due to an inability to maintain pressure on the mouse, but most occurred at the start or the end of the drag-and-drop. Errors at the start are due to the user not knowing whether or not to drag-and-drop or point and click. This can be prevented by adding a short tutorial. Errors at the receptor can be prevented by showing a rollover state, so that it is clear when the target can be released. The receptor should also be larger than the target. The direction of the drag-and-drop also made a difference, as well as the distance between the item and the receptor and the size of the receptor. Dragging down and to the right, and having a larger receptor made it easier. They were unable to show that more errors were made during point-and-click and drag-and-drop.
Our observations confirm the studies. With children as young as 3, we have seen the most errors occur at the receptor, due to not releasing the target at the right time. Rollovers and indicators are necessary. We can make both drag-and-drop and point-and-click accessible. We prefer the point-and-click method for K-2, because the directions are the same as for the accessible implementation, where the user can click on the target, then click on the receptor to place the target.
 Drag-and-Drop vs. Point-and-Click Mouse Interaction for Children (1996) Kori Inkpen, Kellogg S. Booth, Maria Klawe Department of Computer Science The University of British Columbia.
 Drag-and-drop errors in young children’s use of the mouse Interacting with Computers, Volume 19, Issue 2, March 2007, Pages 257-266 Afke Donker, Pieter Reitsma
 Buxton, W. (1986). There’s more to interaction than meets the eye: Some issues in manual input. In Norman, D. A. and Draper, S.W. (Eds.), User Centered System Design: New Perspectives on Human-Computer Interaction (pp. 319-337). Hillsdale, NJ: Lawrence Erlbaum Associates.