Matric to CBSE

This is a common problem faced by the children who shift from state syllabus to CBSE syllabus. In cbse schools as per the norms teaching as well as communication is in English language. So children at a young age find it diificult to understand the subject, esp. science or social when taught in Englsh. For maths there is no such problem. When the child doesn't understand what is being taught, then there will be a lack of interest in the subject. And this will slowly make the child lag behind.
Teachers have to complete the syllabus within a stipulated time, so they rush with the lessons one after the other as per their annual/year plan.
Conserving with the child in English at home, making the child read small stories in English, the stories which the child likes, playing games like word-building or scrabble that will help in improving English language. At the same time the child needs encouraging words. Even at school, if teachers encourage the child for any small work that he has done successfully or tried to attempt, this will make the child happy and thereby help in developing interest in the subject.
In this way once the child understands the language, then he will slowly develop interest in English language and later on develop interest in the subject.
When the child is active, then no doubt he is intelligent too.

Wish you Good Luck.
May God Bless your child !