In Skellig, what are Mina's criticisms of school?
Mina is home-schooled. She likes to quote Wiliam Blake (the poet) quite a bit. One quote she uses puts forth the notion that traditional, classroom schooling steals the joy of learning from students. She has bought into this idea completely. Her parents were of the same mind (her father is now dead) and so when she is schooling at home, she reads, writes, draws, paints, studies animals and their skeletal structure, nature, and even the artistic nature of clay—making animal sculptures. She, however, does not have much in the way of a social life.
Michael is torn as he is completely fascinated (most of the time) by her take on the world. He believe she is extraordinary. Except for her unveiled insults of the public schooling system, and her complete disregard for his friends (due to jealousy? and their taunting of her?), he loves to discuss things with her that she has learned that are not taught in his classes in school.
In this way we can see both sides of the positive elements that home-schooling and traditional schooling offer. And though Mina discredits Michael's schooling often, she is—though unusual—still a caring, gentle-hearted girl, and Michael finds a great deal about her to admire. They become very close friends.