Ahhhh , homework woes. This is a topic that seems to resonate in many households. Here is what I recommend...
1- Let her play first to get out some of her energy before sitting down to do any work. We all need a break after a hard day and school is hard work for kids!
2- Make sure she is not hungry and has had a snack that won't make her "antsy" such as something loaded with sugar.
3- Only expect 15 minutes of sustained attention at this age.
4. Monitor her work. Praise her when she is working. Ignore negative behaviors or redirect her if she seems off task. Never yell or compare her skills to others. She is five and seems to not have learned about study habits yet.
5. Sit down with her and do YOUR work- such as bill paying, reading a book or sending a letter.
6. Reward for attempts and completion of her work.
7. Only help her if you feel that she is really struggling or needs a sample or two of assistance.
Alert the teacher if she still struggles after the consistent implementation of these or other recommendations. (over a week of following these general recommendations or others that professionals may have suggested.)
Good luck and perhaps others will provide other successful strategies, as well.