What are the common existing yoichien assessment practices?

For anyone familiar with the yoichien system:

Hello! I’m an eikaiwa teacher and is unfamiliar with how yoichien teachers assess children’s growth and development. Do they also conduct formative and summative assessment? What methods do they use other than the “log book” (sorry, I don’t know what it’s called) that parents read and also write on?

This is actually an assignment for my graduate program, I tried searching online but I couldn’t find any document about assessment methods yoichien teachers use.

Thank you so much for your insights.

TLTR: Question