SCOTUS struck that down with the Lopez Decision.
Yes, but that was the Federal version. Also, Bill Clinton extorted the Congress to re-pass another version a year later that claimed that it was Constitutional because the Congress said that it was *interstate commerce*. As far as I know, no prosecutions have been done under the second law, and it has never been challanged.
I don't know if any prosecutions have been done under the Wisconsin law.