Progress in learning follows a crooked path, or more precisely a spiral one.
You learn something as an isolated rule in key stage 2, but revisiting it at KS3 turns it into part of a more general pattern, and maybe further visits through life will deepen understanding still further.
That's what it means to say that the best way of learning something is to teach it. We teachers learn something new every day.
A really good example of this is in the "spelling rules" which change the last letter of some words when they receive an affix, producing spellings like "sitting" (two ts), "hating" (no e) and "babies" (ie for y).
These rules can be treated separately, but this is a pity because they actually fit together rather well and support each other. Let's have a quick look at the three rules:
1 Consonant doubling: this doubles a final consonant (except h, w, y, x) after a single stressed vowel: "sitting", but "seating"; "bedded", but "headed" and "beaded" (both of which have two vowels before the d, in spite of their different pronunciations).
What children probably didn't learn at KS2 is that this change happens before any suffix that starts with a vowel: ing, ed, er, est (fitting, fitted, fitter, fittest), and even irregular suffixes such as en, ish and y (forgotten, biggish, bitty).
2 E-dropping: like consonant doubling, this applies before any suffix that starts with a vowel. This is obvious before ing and y (hating, maty), but less so before suffixes which themselves start with e.
To see its effect you have to split "hated" into hat - ed and "later" into lat - er; then the rule is very simple. The e that drops is the one you can't hear - so you don't drop the final e of "be" in "being".
Both these rules have something to do with the last sounded vowel before the affix, which is short for consonant doubling and long for e-dropping.
3 Y to I:this turns y to i as in "babies"; but it only applies when y is pronounced as a separate vowel which we normally write i, so it applies in "tries" but not in "days" or "boys".
What about the e that creeps in after i to give "babies"?
We leave you to decide whether it makes more sense to say that y changes to ie before s, or to say that s changes to es (as in "tomatoes"); and to work out what kind of suffix triggers this change.
Spelling can seem bewildering territory to many of our pupils. The more straightforward we can make it, the more their confidence will grow.
KS3 pupils are already expert spellers - it's just that they may not realise it.