That sounds appropriate for a 4-5 year old. I definitely believe that 4 is not too early to have a child make his/her bed. I think my mom started chores earlier than that with me but it was a battle of wills b/c I didn't really "get it." One thing we do is encourage "helping." Right now they are eager to help bring their diapers to us, bring the dustpan when we are sweeping, etc., but I'm not expecting them to be so cooperative forever! Setting reasonable expectations and allowing the child to fulfill them is what builds confidence, so if she has mastered what she is being asked to do now I don't see why she shouldn't have more responsibilities soon.
Carrie (28), wife to Mark (31), mama to identical twin cuties Ethan and Ryan (27 mo.)