Always make sure that your left handers are sitting to the left of a right hander so that their arms don't clash. Make sure she slants her paper slightly downwards as she's writing. It can often be helpful for left handers to have a cushion to sit on to raise them up a bit. Make sure she is holding her pencil appropriately, that is a major problem for many children these days, both left and right handed. Too often it is the pencil grip being incorrect that means the child is dragging their hand across writing. This is the most likely cause if she can't see question numbers etc.