Charlotte Mason taught Curwen sight-singing with sol-fa, which has since been replaced by the Kodaly method which also uses sol-fa.

The PNEU programmes listed Fifty Steps in Sight Singing, with 2-3 steps worked through per term.

If you are coming in to sol-fa this Form with no previous, start with the resources in Form 1. You and your children will need to have a base to work from.

While the youngest levels of Jolly Music, for example, could be skipped, you will probably want to look at table of contents to make sure your children know the information in these foundational levels.

Another good option is to just work through the lessons from Children of the Open Air on youtube. They also have an informative website, which we encourage you to explore.

Here  is a good article on sol-fa in the Charlotte Mason schoolroom.

Hoffman Academy continues with solfege, so if you haven’t used them for instrument training it is a good program to consider. There is both a free version and a premium, paid version with more features.

Sight Singing School  is an online program. You will most likely need to present the material to your children at this age (note from Marjorie: we used this when my daughter was in high school, and watched the videos and practiced together)

If you have a strong background, here are other resources you might consider (we have not used all of these, they are merely for your consideration, and their usefulness will depend on your own background)