J.C.
Aren't bunks great??? --- try some of the soft- mesh hanging dividers -- they are sold very inexpensively as '''back of the door shoe and ''stuff'' holders--. You wouldn't need the entire length-- just cut off the length you need- attach it to the wall-- put the childs' stuff in the different pockets- and there's nothing to hurt them--- ( a little unconventional- but it would solve the problem of bashing heads)
:-) Old Mom aka - J.