Should a sessional instructor applicant submit a teaching statement? I'm currently a grad student and I was wondering if it is common (or good practice) for applicants to sessional instructor positions to submit teaching statements. The positions I'm looking to apply for do not specifically ask for one (instead asking for a letter of application, listing courses of interest), and it might seem like a good opportunity to also develop a teaching statement, but only if it necessary as I haven't yet taught a course and I'm not entirely sure what I would write about (I do have considerable TA experience).
I'm giving this answer from the point of view of philosophy, in the USA. I'd say that you should include a teaching statement in the packet, unless you are specifically directed to include only the materials they explicitly ask for. Don't bother with a research statement or some of the other junk that comes in a tenure-track packet. But this is a teaching job, and if I'm reading the above correctly, you don't have any experience as the instructor of record. So, what I would try to do is to write a short (1 page) statement that shows a committee looking at your packet that you are ready to walk into your own classroom and do your thing. 

It is really hard to write a good teaching statement. It's going to be even harder without a lot of first-hand experience. Fortunately, there's no end of advice out there on the web. For example, this, and this are both helpful.