Statistics have shown many times over that children whose parents are involved in their education outperform children whose parents do not get involved.
Whether the parents decide to home school their children entirely or send them to school but work with them on their school work every day, their student children have a great advantage because they are taught by the world's best teacher: their dad and/or their mom.
If your parents have helped you by getting involved in your own education, why not let the whole world know that they have made a difference by giving them a World's Best Home School Teacher T-shirt.