Reasons for Transferring

I really want to transfer to be more academically challenged and be a part of a college community with a more competitive student body. But I realize that my current institution offers everything I want to study; it’s just that I want to be more challenged while doing so. This reason seems weak (though honest) because unlike many other transfer cases, I can study what I intend to study. What do you suggest I include in my Common Application essay to make my argument for wanting to transfer stronger?