In the longer version, go into more detail about previous jobs you've held: dates, employer and/or name of school, position and duties performed. Emphasise any initatives you had while in that post. Which curriculum was being followed at each school? You will be able to decide for yourself whether or not to include non-educational employment: if your "longer" CV seems a bit short, it could be worth choosing one or two at least, but be selective. If necessary, create a third, "longest" version and edit later. Voluntary work should almost always be included.
Some employers still ask for high school qualifications so it is a good idea to have these on your longer CV: establishment, course, result and date of each. Details from your college or university transcripts should be added.
Don't forget all that Professional Development you found useful a few years ago, as well as courses you have done in the past that you may not see as directly relevant now. Clubs you have known and loved go here too. What about cross-curricular work? Have you been involved in other school initiatives such as International Day, Maths Week (whether that's your subject or not), camps, school trips (domestic or foreign; educational or fun)?
Activities you've been involved with in the wider community show concern for others, and that you're a social creature (at least sometimes!).