As a child in Canada, I was taught that "plead" and "plead" [pled] were both present and past tense, similar to "read" and "read" [red], and to "lead" and "lead" [led]. I suppose this is just the difference between the British way of speaking and spelling and the American way. Of course, it is their language.

As MesMom2 argues, not all Americans say "I could care less" when they mean just the opposite. However, I do believe it is only Americans who commonly use this expression. I have travelled extensively throughout English-speaking nations and in no other country is this expression comnmonly used.

Many years ago in Canada, where I went to school, the present and past tense were both "lead." The past tense was not spelt (spelled?) "led." Also, the present and past tense were both "plead." We never heard (heared?) nor read "pleaded" or "pled."