Hello aspirant,
Yea some schools do have written test for admission in class 6 especially for reputed private schools or government residential schools. And if they're having a test it is very essential to clear the exam. However the exam may not be hard. It will be based on the Class 5 syllabus. With a little preparation with focus you can surely clear it.
Also keep in mind to cover your basics and practice in reading comprehension.
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