I used to travel for a long term substitute position. I was traveling between 12 schools and was covering K-12 for adapted PE. What I found to be the easiest when I needed to provide written work was to prepare the written assignments prior to the start of the year. I would give them to the detention teacher to give to the students when they came. It was a lot of pre-planning but found this to be effective. Depending on the grade level there are a ton of online resources (Edhelper.com is one, PE Central is another) that you can get a variety of assignments. I hope this helps.
I loved traveling to see different programs and ideas but did not like that I did not have a program of my own.