Does it even really matter if kids use underhand means to get their grades? Bear with me on this...
Let's say one child studies fanatically for two years and gets an A.
That grade reflects his ability to research, collate and apply information in a cogent way. As a result, he is given a job. Asked by his boss to compile a report on, say, farming in Europe, he'll be able to go away and come back with what his boss asked for.
Then let's say another child plagiarises his coursework and also gets an A.
That grade reflects his ability to take short cuts and get away with it. As a result, he is given a job. Asked by his boss to compile the same report, he'll go away, not bother with research and probably cut and paste from the internet, before giving his boss what he asked for.
Either way, the boss gets what he asked for - so you could argue the grade reflects the ability to complete the task. It makes no difference if one 'cheated' and the other worked hard.
Or is that utter horsesh*t?