As my wife, kids, and friends will tell you, I sometimes rant about grammar. I'm going to do that now, so excuse yourself now if that kind of thing bothers you.
Don't worry. I'm not going to lecture you on splitting infinitives or beginning sentences with conjunctions (neither of which is improper, by the way, but never mind . . . ). My latest concern is not a technical grammatical point, but a simple question of proper English usage.
The past tense of the verb "lead" is spelled "led," not "lead."
Napoleon leads the troops into battle. (Present tense)
Napoleon led the troops into battle last week. (Past tense). NOT Napoleon lead the troops into battle last week.
People seem to be using "lead" as the past tense more and more. I have seen it not just in student drafts and blog posts, but in newspapers, books, and other sources edited by people who ought to know better. I'm not sure what the problem is; perhaps people are analogizing to the verb "read." The present tense and past tense of that verb are the same. Or perhaps they are comparing it to the element "lead," which is also pronounced "led."
Whatever, the reason, it's not proper English.