My 5th graders are working on extended do pentatonic. I'm always telling them I've "grown" them because this is my third year with them and they are just doing wonderfully - definitely strong musicians and performers.
Anyway, at the beginning of the lesson, they work on a sight-reading example as a class. I've based it on my "solfa dojo" (it corresponds to "recorder karate" which they are familiar with). You can find the idea on my TPT store and download it for free.
First, the students chant the rhythm of the song (they can earn 1 to 3 points for this).
Then, the students chant the solfa of the song (they can earn 1 to 3 points for this).
Lastly, the students sing the song on the solfa with hand signs (they can earn 1 to 3 points for this).
This has been going very well with my kiddos (we're on our green belts now). Before they perform each section (rhythm - chant solfa - sing solfa) they are allowed to discuss the answers with each other. It is just totally precious to hear them talk to each other - for example, "No, that can't be a mi because it isn't on a line and do is on a line" or "That's a la - see how high it is?"