The key thing to remember about writing is the relationship between sounds (phonemes) and letters (graphemes) or phoneme-grapheme correspondence.   As with spoken data, look for what the child is showing understanding of, not just what they’re missing.  Some things to think about are:

Spelling patterns in English

There are often several ways of spelling the same sound (e.g. or, al, au and aw can all sound the same: for, walk, autumn, saw).  Remember the difference between digraphs (2 letters, 1 sound e.g. ch) and blends (2 letters, 2 sounds e.g. br).  Discontinuous digraphs require 2 letters but the letters are not next to each other (e.g. the difference between hop and hope - this used to be taught as ‘magic e’).

Stages in Writing

There are various theories of stages in writing, e.g. writing: scribbling, emergent, copy, independent or Kroll’s: preparatory, consolidation, differentiation, integration.  Kroll’s model covers a longer time period, running into high school age, while the four-stage model focuses more on the beginnings of writing, with the first three stages equivalent to Kroll’s first.

Conventions of writing

Children learn that English writing runs from left to right and top to bottom.  They also learn that words are separated by spaces and to use capital letters and full stops.  Many of these conventions are followed before a child is able to write independently.  As children’s writing develops, they may incorporate conventions of stories read to them e.g. collocations like “once upon a time” and repeated constructions like “long long ago”.