Studying too much makes children feel tired and difficult to concentrate on their lessons. They need to relax and do what they are interested in.
Sports would make students feel tired more than studying would.
They may find the lessons interesting and ease to remember.
Really? I would think that children would be more bored after a fun sports session.
Moreover, sitting in one place and studying makes children get fat if they don't play sports
Not necessarily. Growing children do not necessarily needs sports in order to gain muscle.
You should tell us your reason for writing this essay.