Matt Hurt’s review published on Letterboxd :
The Kindergarten Teacher is the best performance I've seen from Maggie Gyllenhaal in a long time. Lisa is soft spoken and adept at covering her unhappiness and lack of creative spark with a veneer of well-meaning drive for nurturing.
But in reality, her interest in Jimmy's talent is solely about her and what she feels she's lacking in her life. Gyllenhaal does a wonderful job bringing us into Lisa's warped mindset in a way that doesn't feel warped. The logic the character employs tracks so well that even when she does morally reprehensible things, they are still grounded within the fragile psyche of our lead character.
The Kindergarten Teacher is an interesting story about a woman whose drive to do and be more than she is leads her to project her deepest doubts and insecurities onto a child and the dark path that it leads her on. The movie isn't a thriller, nor is it sensationalized. However, the deeper Lisa goes to nurture Jimmy's gift and her own fragile ego, the more surprising and tense the movie becomes.