Even if your daughter's only problem is an attention deficit disorder she may still be eligible for some help in school under federal law (Section 504 of the Rehabilitation Act of 1973). Contact the national office of Children and Adults with Attention Deficit Disorders (CHADD) at 1-800-233-4050. There are branches of CHADD across the country where you can get help and information. It's really helpful to have a chance to talk with other parents who are going through the same struggles with their kids.
For specific tips on how you can support your daughter, have a look at Harvey C. Parker's book, Problem Solver Guide for Students with ADHD or Betty Osman's book, Learning Disabilities and ADHD: A Family Guide to Living and Learning Together. There's also a wonderful book that you might want to suggest to your daughter's teachers: How to Reach and Teach ADD/ADHD Children: Practical Techniques, Strategies and Interventions for Helping Children with Attention Problems and Hyperactivity by Sandra Rief. There's even a video that goes along with this book that shows effective strategies in action.