For much of this school year, I have been trying to get called in to substitute long-term. The reasons are practical and many- I get more experience working as a teacher by being able to be in the same classroom for a period of time instead of one day, I get to wake up each morning knowing exactly where I am going to work, how to get there, what time, etc 
, and I get a steadier paycheck out of it.
From what I have observed, the best and most consistent situation to have to clinch this arrangement is to substitute for a teacher who is on maternity leave. Quite a few teachers in their 20’s are having babies, and humorously enough their desire to reproduce means that I have an opportunity to get guaranteed work for more than just one day at a time. Right now I’m in that situation. Ironically, the woman I am subbing for is having a difficult pregnancy, which gives me the opportunity to substitute long-term. Supposedly, she will be out for the rest of the semester, and hopefully if I don’t in fact get called in for jury duty (I am crossing my fingers here) then I might be able to substitute long-term, which would be wonderful experience for me.