Mr. A is well-known for being a strict teacher, and B's attitude is so bad, so it might be good for Mr. A to knock B into shape.
Everyone knows how strict Mr. A is, and B has such a bad disposition, so it might be good to have Mr. A straighten out B's bad attitude.
この場合、次のような言い方ができますよ。
ーMr. A is well-known for being a strict teacher, and B's attitude is so bad, so it might be good for Mr. A to knock B into shape.
「A先生は厳しいことで有名で、B君の態度はとても悪いので、A先生に叩き直してもらった方が良いかもしれない」
to knock ... into shape で「叩き直す」
ーEveryone knows how strict Mr. A is, and B has such a bad disposition, so it might be good to have Mr. A straighten out B's bad attitude.
「みんなA先生がどれだけ厳しいか知っていて、Bはとてもたちが悪いから、A先生にBの悪い態度を正してもらった方が良いかもしれない」
to straighten out「根性を叩き直す・…を正す」
ご参考まで！
カナダ 
