There are no controlled studies of the effectiveness of homeschooling as an educational option, nor, because of the complexity of the problem (exactly which variables can or should be controlled for?), are there likely to be.
There are, however, numerous studies comparing the achievement of homeschoolers and schoolchildren on a variety of standardized tests. Generally, homeschoolers tend to score as well or better than those conventionally schooled.
Perhaps more useful are the performances of homeschooled students as they enter college. Homeschooled students are eagerly sought by many selective and highly selective colleges; they are reported to be more focused and more self-reliant than schooled students, and to adapt better to living on their own.
Homeschooling mother and author, Tammy Takahashi, blogs:
Does homeschooling work? It depends who you ask.
How do you know public school works? Will it work for your kids? How do you know? How do you know that reading this blog will work? How do you know if anything will work?
Jennifer Sutton, of Brown University, writes in the Brown Alumni Magazine Online:
Homeschooling Comes of Age
Teaching children at home is no longer just the choice of religious and political iconoclasts. Now, drawn by Brown's tradition of independence and self-direction, a new generation of homeschoolers is arriving and thriving on campus.
Any teacher can tell you that the children who do well are the ones whose parents are involved in their education. Parental involvement in homeschooling is very deep. The best teachers for all children are people who love and care about them and who respect their particular way of learning--people who have the time and the patience to provide one-on-one attention. Homeschooling parents do what teachers wish they could do in the classroom but cannot for lack of time and help and an excess of students.
Parents do not lightly make the decision to homeschool their children. They realize that it is a big undertaking and responsibility. But for homeschooling parents, the task of helping their children learn is seldom a burden. Children who are given the opportunity to follow their own interests, to dig deeply into topics that interest them, to have some say in how they learn, become eager and effective learners.
It is a myth that homeschooling parents do all of the teaching. Most parents know when they are not the best to handle certain subjects, and they get help, either from other family members, from friends, or from the extensive resources available, such as online instruction or community college classes for older children. The job of the parent is to help find the tools and resources that will help their children succeed.
It is also a myth that having a credential is necessary for homeschooling parents. The bulk of coursework for a credential prepares the teacher to teach a large group of children, and to prepare formal lesson plans meeting state standards far in advance. Parents working with their own children don't need to learn classroom management. They also find that the freedom to change the lessons to meet their children's needs or interests is one of the most wonderful things about homeschooling.
Most homeschooling families consider socialization to be one of homeschooling’s great advantages. Instead of spending the better part of their days in close contact only with others of their own age, homeschooled students have the time and freedom and energy to get to know people of many ages and backgrounds. With more say in the direction of their education, they become more self-reliant and self-confident, and less dependent upon peer approval than most school children.
Few, if any, homeschoolers are isolated to the point where they don’t interact with other people. Most are heavily involved in their communities. They belong to Scouts and church groups, take swimming and dance lessons, play on soccer and softball teams, etc. Many do volunteer work, such as visiting convalescent hospitals, shelving books at the library, even helping at public schools.
Homeschoolers also get together in support groups, to take field trips, hold park days, and for other group activities.
They build deep and meaningful friendships, with more time and space to talk and learn from each other than would be possible in school.
Most parents who withdraw their children from conventional schools report that their children quickly learn to get along better with a wider variety of people--siblings, older and younger children, and adults of all ages--as homeschoolers than they ever did as school students.
There is a large and growing educational market serving homeschoolers, with well-tried curricula and study programs for every educational philosophy. Homeschoolers who participate in public school programs such as charter schools and home study programs have access to a wide range of conventional materials, and many independent homeschoolers take advantage of used book depositories, where they can obtain used school materials--textbooks, encyclopedias and other reference tools, library books, etc.--at nominal expense. Educational television is also a favored resource, as are the Internet and the World Wide Web.
But homeschoolers also go out into the community and the world for their learning resources. The local library, with its selection of books, videos, and other materials, as well as the lectures, reading programs, and other activities often offered, is only a starting point for most homeschoolers. National, state, and local parks provide both formal and informal opportunities for learning. Local recreation departments offer many classes and athletic opportunities. There are museums to visit, farms and factories, science fairs, and more. Community organizations--garden clubs, choirs and other music groups, 4-H, hobbyists and activists of every variety--offer learning opportunities limited only by homeschoolers’ time and energy and interests.
Homeschoolers are not limited in their use of resources by governing boards or editorial committees, and have the entire world as resource for learning.