We didn't do much with numbers for our first week...mostly worked on how to understand directions and writing. We did a couple of worksheets and our sticker book.
Needed to teach my new writer where the top, middle, and bottom lines are. Also, when we hit one of the top or bottom lines I say "bump". I will also say "froggy jump" if we have to lift the pencil. When writing a new thing, have them watch you or a tutorial first, then have them practice.
We also did a worksheet where we circled groups of one. We talked about the concept of zero. I put groups of animal crackers together and let them say how many were in each group, then they could eat the group.