Schools do not teach effectively. Most of the time is spent preparing the children to learn without doing much in the way of actual learning.
When the teaching begins there is usually only one way of learning something. People all learn differently (auditory, kinetic, visual) and I believe this sets some children up for failure.
In a school there are too many distractions and one teacher cannot keep track of what 30 kids are doing at once. (I know I was drawing and passing notes when I was supposed to be learning math).
School at home can be taught much faster to cover a full day of in school learning. As little as 3-4 hour days to be exact with no homework. School can also be taught during the summer so you don't have that giant gap of learning time lost.
Kids learn from one another in school and this can be dangerous. I used to help my friends with their assignments and visa-versea and then we would all get it wrong. Team work is only effective when everyone gets it from an adult first. There is also pressure to be funny and disruptive in classes full of students. Parents can better discipline there kids when lashing out begins.
Children do not have to go to school to learn social rules. There are plenty of groups, sports, and even playgrounds where they can be with similar aged kids.
I believe schools are infested with ill mannered, bullies of children who are not there to learn but interact. I don't want my child to be told that he HAS to be put in the position to feel small or get in trouble for beating on another kid who was bulling him (like I was). As an adult sure we have to do some things we don't like (and my kid will do these things too) but we certainly do not have to be belittled by others and I want my child to have this confidence.
Homeschooling allows parents to fulfill their roll of training up their kids. The bible tells parents to train up their children but how can they do that well if they only see them 4hrs a day and have no clue what they are being taught? I am homeschooled and am so glad that my parents made that decision years ago. Homeschooling allows for children to learn at their own speed and time and for parents to know what their child is learning. While school might be necessary for some families I think that the option to homeschool should aways be left open.
Schools teach children and teens many more lessons than what is learnt in text books and within numbers. Schools teach students respect for authority, efficiency, to take pride in work, time management, and valuable social skills.
The idea that a child will be sheltered from the outside world during the key time of their development is unfair to said child. Being around the peers of the student teaches them how to get along with those who do better than them, and those who do worse, allowing them to learn to respect all others.
In the case of having the parents of the child teach them their school work, the teachings that can go on are very biased. In the example of history or social studies lessons, a parent could speak only about their preferred views on the past, per example, only teaching about the good a political leader did, and refraining from the opposing sides, etc.
In conclusion, there is more to school than just numbers and books. School gives life to young ones, and teaches them to be sent off into the real, working world.
Socialism is what keeps the world going, without it nothing would get done, and people wouldn't be able to get jobs. Public schools teach you how to tolerate people especially if you would need to tolerate a boss with a job. Homeschooling clings on to kids so that they aren't able to talk right to others, makes them afraid of the outside world really. Public is best. Guaranteedm.
Or the lack thereof. Parents are not specifically required to know anything and there is no standardized tests for parental knowledge. While there is a form of standardized testing for students because it is sent to the home the parents can do the tests themselves, help with the tests, and ultimately cheat the system. This is worsened if the parent cannot or does not know a lot on any given subject they are trying to teach and even innocently misconstrue the information packet because they themselves did not understand it.