Before school starts, draw a LARGE shape such as an apple. Cut up the shape into pieces like a puzzle. Send each child a piece of the puzzle. Include a note to the child asking them to decorate the puzzle piece anyway they want and bring it with them on the first day of school. When all the puzzle pieces come in, reassemble the shape on your bulletin board.
I suggest a theme such as “I am new, you are new” for your first week. Bring in a poster board filled with pictures of your family and label–husband, kids, pets, your favorite chair, your kitchen, etc. Before your kids arrive, get a list of address’s of your kids and send them a note and ask parents to send in a family picture on the first day. As you get to know each of your kids that first few days, you can put the family pictures up on a poster board next to yours, showing the kids how we are alike and different, opening lots of conversation opportunities for your circle times etc.