A 1-3-10 Free Write is a great activity to leave for a sub (as long as your students are trained and you leave clear instructions!!) because it takes quite awhile to do. It is beneficial, but I have a hard time justifying chunking out such a long period of class time when I am there and can be input-ing Spanish into my students.
I created this form for my students to use when they do a free write. It has the instructions written in case they are tuned out when they are explained. I have one form that is one-sided and does not contain any rubrics, and then one form that is two-sided and contains rubrics (different back sides contain rubrics for the different levels I teach.