Aw! This was super kind, and I like the idea of stressing proportionality. It's nice to be told that the abstraction can wait - I've felt like I should be abstracting more at times, but it's not my natural instinct, so it's nice to be told I'm doing things right on that front! I feel the same way about anyone who can teach older (or younger!) mathematicians - keep on keeping on.
Oh, I really mean it. Teachers to children (and especially maths teachers) are essential for our society, and have one of the hardest job.
Focusing on proportions you can teach almost anything: from basic triangle geometry, including elements of what later they will know as 'trigonometry', to interest rates -even letting the best get the scent of 'compound interests'-, to areas & volumes to the notion of 'speed' as a ratio, to how to save money for the future... There is little more a normal 'literate' person needs to know, as I see it.
However, it takes quite an effort getting them to actually perform the computations. This is where 'good' -appealing- exercises and problems are required, and this is where the teacher's craftmanship comes into play. A good craftman will find the correct and 'fancyful' exercises, according to the class, the student, the time... You know, this is where the 'heroism' takes place.
Really, the most important thing you can teach is the context behind the maths. Find examples in real life of where the maths is applicable; spend 3/4 of a lesson explaining the backstory as to why we do things the way we do. Students lose their way because maths is presented as an endless series of facts to rote learn, with no context. There's a thriving backstory of human ingenuity behind the numbers and operations which sadly gets little or no time in the classroom.
Read Bill Bryson's book "a short history of nearly everything" for an example of the style I wish my maths classes had been taught in. It's a survey of science book, but mostly focuses on the human interaction behind the discoveries & theories, and makes fascinating reading because of it. We need to teach maths (and all hard technical subjects) closer to this approach.
