Time does not have to be spent on test taking at all unless it is something the child wants to do. In a classroom, testing is the way the teacher finds out how much the students have learned. Observation and discussion are ongoing at home, tests are unnecessary. Tests can be used by the child to see how much she recalls and to determine what to study next. Grades are unnecessary and there is no comparison of test results.
Grades become of no importance and learning is motivating in and of itself.
Skills and concepts can be introduced when the child is ready for them. She does not have to wait until a certain grade level for learning something which she is interested in and ready for right now. Children will learn how to devote their energies and time to activities they think are worth it. This should keep you busy. I have pics of some of their statues on this page.