What are you trying to teach her? Is she struggling in certain areas?
If you are just teaching to provide more education, and if you are doing worksheets/flashcards/traditional methods, try thinking outside the box. Experiential learning is almost always better received than book learning, IMO. Get an ant farm, grow some seeds, plant a garden, go lay out in a field at night with binoculars or a lower-powered telescope and look at the stars. Make band instruments out of cardboard rolls and boxes and rubber bands. Take her to the zoo with a sketchpad and ask her to draw a few of the animals she sees. And add what they eat. Or whatever seems fun. And so on.
If she is struggling in certain areas, it's best if you can hire an outside tutor to help. Kids often think they can slack when it's their parents telling them what to do, but will respond much better to a "teacher."