The phrase "kindergarten level" refers to something that is very easy or basic, similar to what a young child in kindergarten would be able to understand or do. Full definition
One of the most important areas of knowledge that developing readers can develop at preschool and kindergarten levels involves learning the various forms and functions of written language (concepts about print). (ciera.org)
At kindergarten level, the children are learning how to word process. (edutopia.org)
In Math K, students cover kindergarten level content in Math. (idahoidea.org)