Hi Debi- Words of encouragement are awesome. Even if you are frustrated with your daughter, finding a way to encourage her or say something positive is so important. Incentives, like cell phones also help. Lots of info on how to help with homework here: http://www.schoolfamily.com/blog/author/Angela Norton Tyler/
I have the same problems with my 4th grader, she just say that all her work is in her desk and that she just forgets to trun it in. She have stayed behind one year already due to the tasks testing that they have and now I tell her that if she dont get her stuff together and do her work and turn it in, that her brother will be in the same grade with her the following year and does she want that. I just keep telling her that she is smart and that she is very bright and I know that she can do it. And i just keep telling her that everyday and now she is starting to do it, cause like i told her I cant be there and do it for her she is old enough to do this and she has to show that she can be responseable if she wants a cell phone when she gets to middle school or so on..