Public School４９０万円×５年間＝２，４５０万円、大学の費用１，６８０万円。合計４，１３０万円
日本の私立中高一貫校の費用を塾の費用を含めて考えると９００万円ほどでしょうからアメリカ大学の費用３千万円と合計すると３９００万円になります。
両方を比べると大差ありません。しかし、イギリスに１３歳から留学する場合は問題があります。名門大学に入るには名門Public Schoolに入る必要があります、その名門Public Schoolに入るには、通常は１０歳で受験しなければならない場合が多いのです。
日本の学校にいて名門Public Schoolの受験が果たして可能かと言えば、ほぼ不可能です。
従って、１３歳から留学する場合は、進学先が必ずしも名門Public Schoolというわけにはいきません。
ある名門Public Schoolは１０歳を過ぎても応募できるところがありますが、２０２１年９月に入学するには２０１９年１０月１日が応募締め切りで、２０２０年の４月中旬に English and Mathsの 試験があります。
下記は、その英語の試験に出た英文です。日本国内の学校で学習していて、この英文を深く理解できるでしょうか？
In an armchair, with an elbow resting on the table and her head leaning on that hand, sat the strangest lady I have ever seen, or shall ever see. She was dressed in rich materials – satins, and lace, and silks - all of white. Her shoes were white. And she had a long white veil hanging from her hair, and she had bridal flowers in her hair, but her hair was white. Some bright jewels sparkled on her neck and on her hands, some other jewels lay sparkling on the table. Dresses, less splendid than the dress she wore, and half-packed trunks, were scattered about. She has not quite finished dressing, for she had but one shoe on – the other was on the table near her hand – her veil was but half arranged, her watch and chain were not put on, and some lace for her shoulders lay with those trinkets, and with her handkerchief, and gloves and some flowers, and a Prayer–book1 , all confusedly heaped about the looking glass. It was not in the first few moments that I saw all these things but I saw that everything within my view which ought to be white, had been white long ago, and had lost its lustre2 , and was faded and yellow. I saw that the bride within the bridal dress had withered like the dress, and like the flowers, and had no brightness left but the brightness of her sunken eyes. I saw that the dress had been put upon the rounded figure of a young woman, and that the figure upon which it now hung loose, had shrunk to skin and bone. Once, I had been taken to see some ghastly waxworks3 at the Fair. Once, I had been taken to one of our marsh churches to see a skeleton in the ashes of a rich dress, that had been dug from under the church pavement. Now, waxwork and skeleton seemed to have dark eyes that moved and looked at me.