Public education in the majority of countries does not include any religious education, so parents who want their children to receive it along with public education have few choices. While religious institutions often offer private schooling, it is not affordable for many families. Rather than have their children confused by the information taught in public school systems, parents who do not have the wealth to enroll their children in religious school systems teach them at home.
Countries with public school systems often have a mandate of how much information a child must learn to graduate, and children schooled in the home are given tests to ensure they learn as much as those educated in a formal setting. Religious education is not part of the testing procedure, and it is up to the parents or their religious institution to determine if a child has learned enough. Mandatory tests are on subjects such as reading, writing, mathematics and history.
The business of homeschooling has been growing in the last few decades, and parents who take their children out of public systems have a large network of support. Books are often provided at a discount by religious institutions that support their choice, and the internet offers them a way to find programs that will best help them.
While teachers in public schools are usually required to have a college degree and teaching certificate, parents educating their own children have no special qualifications. The state only demands their children pass the same educational levels as those in the public system to graduate from mandatory schooling.