When it comes to kids' beds I've learned a few lessons over the years.
1) Beds are not only for sleeping but for storing trash, library books, legos, socks and anything else that may find it's way there by intent or by accident. In the worse case scenario even food might be discovered. Therefore, if a child is to truly clean under her bed it must be located away from the wall and be lightweight enough to move (preferably on her own).
2) A child will only be able to make their bed if it is achievable. Many pillows and sheets will deter any child from success. Therefore, a medium weight comforter is sufficient.
3) Children are naturally attracted to bouncy beds. Don't give them a box springs and suddenly the bed ceases to be a trampoline. Besides, I'd much rather spend the money on a better quality mattress than on and cheaper set.
4) Headboards bring out the artist in a child. It's not only a perfect surface for creating art work, but also for displaying other things like gum and stickers.
On my quest for beds I found myself drawn to this simple design. IKEA has several similar bedframes. This one ranges from $115-$179.
With the help of a handy husband, we made our own using this pattern. We bought the materials for the first bed at Lowe's for just under $50. Then we went to Menard's where the lumber was on sale and spent $40 for the remaining two beds. It took Sean about 2 hours per bed. Well worth the effort!