4-H has a nice manual for learning to sew. You can also find free learning to sew lessons on line. I would start with that. Then I would kind of see what the girls are interested in. If you are using your machines you have already cleaned and oiled you might wait until you have something to clean and oil - if they are bringing their own machines you will need to make sure they have been cleaned and oiled before you try to sew. I start with sewing on paper.