That Spelling Thing is for anyone who is not an emergent speller - around 8 and up. (This is unlike That Reading Thing which is can't be used for younger than 11.) So, if you teach years 3 to 6, you can have a lot of fun cracking the code and setting in place spelling strategies that will last a lifetime.
Secondary - Any & All Subjects
That Spelling Thing is for any teacher of any subject who wants their students to master both everyday and specialist curriculum vocabulary. TST started because a science teacher asked, "Can you please get them to spell 'fractional distillation'? Yes, we can.
Post-16 Phonics & Adult Literacy
That Spelling Thing is especially empowering for older learners who've always felt nervous about their spelling. 16 or 60, this memory friendly method will help them self-calm to overcome that anxiety and conquer spelling once and for all. It's life changing for people who've never felt confident filling in a form.
"By the end, even if you’re a weak speller yourself, you'll feel confident enough to put this spelling guidance into use, in your own classroom, immediately." ~ S Godsland, dyslexics.org.uk