I am not sure it necessarily has to do with increasing cognition in that it is measurable with an IQ score. I do know however that the students we see enter kindergarten after being in a preschool program are much more ready to learn than those who have not been in a preschool program.
If parents at home are exposing their children to stimulation by talking with them, reading to them, and using everyday occurrences as opportunities to teach, they're achieving what a preschool cannot because parents are the most influential people in a child's life. This means parents are teaching things which will serve as a foundation for all other learning. If teachers are doing these things in lieu of parents who are not, that's a good second choice. If children are at home but getting no mental or emotional stimulation, a preschool is perhaps a better choice. In general terms, parents educating and preparing their own children is better than putting them in classrooms before they need to be.
In agreement with post #3, this statement needs qualifying. Certainly, programs such as Head-Start are effective in developing cognitive skills in low socio-economic children because in their home environments they are not nurtured or exposed to many learning situations.
Socio-economic environment is not the only factor that must be considered, either. Genetic makeup and maturation are also factors. For instance, studies show that many male children are simply not physically ready for reading as their eyes have not yet developed the ability to focus on a page. In fact, experts advise that boys not start reading until age 7.
I disagree with this statement. We only have to compare our education system with such countries as Finland and Denmark, where structured schooling begins at age 7, to see that pre-school education programmes are overated and do not give children any long term advantages. Children in Finland and Denmark only start to read when they start school, yet it is internationally recognised that they have some of the best educational systems in the world.
I disagree with the statement, but that does not mean I think that those who remain at home will advance more than ones who attend school. Rather, I think that this is too broad of a statement and it can never capture the variety of experiences that various children might have whether at home or in a school setting.
In my opinion, the development of cognitive skills depends completely on the quality of the teaching and the curriculum (in addition to the student's own native abilities). I do not think that we can make any blanket statements as to which teaching and curriculum (preschool or home) is superior. I think, therefore, that there is no way to generalize.
I would tend to disagree with this statement, because we cannot assume that parents are not educating the preschooler at home any less successfully than in a school setting. Since children mature and develop socially and cognitively at different rates, sometimes a preschooler is better off staying in a home environment, just as this is sometimes true for those who delay Kindergarten a year.
There are other social environments beyond school, both in the family, the community and through networks of friends that kids can be socialized through. Some would even argue that kids socialize in small groups anyway, even in a larger school setting, therefore the same socialization can take place in the home that takes place elsewhere.
Students who learn and acquire language skills more quickly, for example, might also be stifled in a public school setting geared towards teaching students at a lower or middle level, where in a home environment, with the right support, they can advance at their own rate.
I would disagree with this statement that it is not the education that matters most but the role of the teacher. There are teachers in say LA, California, for example, that have the lowest socio-economic students with just about all types of parents from caring to jailed that the teacher seems to be able to motivate to learn. All other factors are secondary as long as the teacher provides a learning environment.