Why do you, and they, care so much what the notes are called? This is moving from one code, written music, which has a spatial relationship to pitch, to another, note names, which is a step further from the pitch of the notes. Of course names are useful for communicating, but I think the mental connection between the printed music and the sound, or strings, is more important.

On the rare occasions I have taught music I make great use of landmark notes, starting with the Cs and Fs, navigating by interval from the previous note and pattern spotting. Eventually, and hopefully, any note will become a landmark as appropriate, but also players realise there is no need to actually read many of them individually.

Years ago I made little packs of what might be called flash cards but really were something different. They were each small vertical rectangles that fit exactly over the piano (or keyboard) white keys, on heavy (67 pound) paper. All were white, except red for all C’s; blue for all F’s. Printed on one side only, each showed the image of a note on either a treble or a bass staff. The note varied from a whole note through smaller values with the smallest being a 128th note. (there are two of these used by Bach in the first movement, the G minor Adagio, of his “Six Solo Sonatas and Partitas for Violin”, Peters Edition). With varying uses, by different levels of students, note-reading progress was usually rapid, especially having them place, beginning with Middle C, the correct card on the correct key, and pressing the note to hear the sound. Then by matching that sound to their plucking of the matching harp string, they had learned the name, sound, image on staff, left or right hand, note values in written music, location of that sound on harp geography, etc. As the student progressed and also took these cards home to practice, I could then start timing them to either complete the whole pack (60 cards) being laid down correctly on the studio piano, or plucking elementary level harp music (one finger at first) while saying the name of the note out loud.. Most of those card packs were never returned, but hopefully used as a kind of game by family members afterwards..