Colorín Colorado describes the definition and importance of Informal assessments “(also called authentic or alternative).
Informal assessments allow teachers to track the ongoing progress of their students regularly and often. While standardized tests measure students at a particular point in the year, ongoing assessments provide continual snapshots of where students are throughout the school year.
By using informal assessments, teachers can target students’ specific problem areas, adapt instruction, and intervene earlier rather than later.”
https://www.colorincolorado.org/article/using-informal-assessments-english-language-learners