I am a special educator and the parent of a child with a mild learning disability and attentional difficulties. You have received some very helpful responses. First of all, let me say you are not alone. There are very intelligent children everywhere who have mild learning disabilities and difficulties with focus, attention, and organization. I teach them and I live with one. These kids have average to well above average intelligence but for some reason they do not always achieve as well as their IQ's indicate that they should. Having an IEP and specialized services at school will help this. It also requires heavy parental support...which you are giving.
It sounds like the main difficulty your daughter is having right now is with organization, memory, and attention to detail. Your description reminded me of my son around 3rd grade...he's 17 and in 11th grade now. I would tell him to go get his shoes and he'd return with something totally different. He has always needed help remembering and keeping information "sorted". When he was identified with a learning disability, I also had him tested for an attention disorder. He was never active or over active, just inattentive. Tests showed he is ADD (inattentive type). He started medication at age 9 and still takes it today. He will tell you and anyone else that the medication made a wonderful difference in his life. In his words, "When someone asked me a question or to do something, everything I had learned in my entire life was rushing through my brain while I tried to find the correct response. My medication helps me to sort information and pull from the correct place. It makes retrieval more efficient." My son, like your daughter, could handle things academically. The poor organization and inattention caused most of his difficulties in school. Once he started taking medication, the "learning disability" part seemed to go away...those gaps closed.
I have watched my son do many things on his own to compensate for this attentional problem that will be with him for life. He carries around small pieces of paper with words or notes on it so he won't forget to feed his fish or get gas. He writes on his hand. He asks us (and others) to give him one or two directions at a time. If I give him a list of jobs, he may say, "I'm taking out the trash and getting the mail. I'll come back and ask you to repeat the rest when I'm finished."
On medication: It's definitely a personal choice! People with a diagnosed attentional disability are lacking a chemical in the frontal part of the brain that the rest of us have. Just like a diabetic needs chemical regulation in order to live, folks with attention disorders need that chemical to be able to remember, attend, and focus properly. I don't see it as "drugging". I see it as medicating a health issue that is necessary....restoring a chemical that isn't in the brain that should be in the brain. I chose to give my son medication to restore the chemical to his brain...just as I would have if he was diabetic, had a heart problem, or had high blood pressure. He has thanked me many times for helping him to help himself. I'm glad I didn't watch him struggle for years because I was afraid of what others thought about me as a parent.
Sorry, back to you. Having extra books & materials at home is an excellent idea. I like the backpack buddy idea too. Can her teacher made her a buddy for someone using her strengths so your daughter can see that we all have strengths and needs and we help each other out? Does your school subscribe to online versions of text books/workbooks? If so, get the username and passwords and utilize them. In an emergency, are there other 5th graders near you/in your neighborhood who would loan her the book when they have finished their homework? Is there some kind of physical reminder (like the old string on the finger reminder) that will help her to check for homework books before she leaves?
Good luck to you. Great things are possible. I was in your shoes several years ago and now I see a bright, capable young man doing extremely well in high school and preparing to apply to college. Most of the time he's so independent that I can't believe that those earlier years even existed. Hang in there.