The term "Clean Slate" is an idiom. Its origins lie in the fact that people (mainly students in the 18th and 19th centuries) used small rectangular slates (like small chalkboards) for their work as pencils hadn't yet been perfected and as we all know, students need to erase a good amount. The idiom, "Start with a Clean Slate" comes from erasing all previous problems and issues and starting over again.
This applies to my classes because this is a totally new year. For the most part, your teachers don't know you. Even if they do know you or are aware of a reputation, for good or bad, you get a second chance at a first impression this year. Be sure to take advantage of your fortune and let's all start off on the right foot.
I'm looking forward to a great year, and hope you are as well.
