First of all, the current school education makes children lose interest in learning, homework is too much to finish, exam-oriented education and so on all make children feel that they are suffering. The child is only in the third grade, so you can find a small tutor. Don't listen to what they say, how many points will be improved in many days. It's all a lie. Find a small tutor who can solve problems for children attentively, and let the tutor practice the mathematics knowledge that children have learned in different categories and topics. Only those topics that children have mastered well and those that are weak are purposeful tutors.

Secondly, the child's math performance has dropped, so give her more encouragement. Do not push her. She is more anxious than you. Buy her some extracurricular tutoring materials. You study with her. When I was a child, my mother accompanied me to study. Every night, I find a few representative topics to do with her. Representation is very important. If the child can't teach a question, don't scold her. The child's mood is the most important.

Finally, now that the Olympiad has been cancelled, no matter how many children study, you should not let them study. I think it's better for children and stressful. Early deep intellectual development will make children lose interest and even affect their intellectual growth.

I hope my answer is helpful to you.