Eye contact itself is a kind of communication. Experienced teachers can usually communicate with children with their eyes, and children can understand what the teacher wants to say through the teacher's eyes.
Parallel to children
When communicating with children, the teacher's line of sight should be parallel to the child's. The best way is to squat down and communicate with children, so that children can feel the teacher's attention to him, be equal to the teacher, and feel the teacher's concern more when communicating.