The school should have very clear objectives. It is different from a general school, and what makes it special is that its main objective is to bring up children with kindness and to raise them to be kinder, more loving, and compassionate toward others. The aim is to develop a thought of universal responsibility, so that each child feels responsible for every living being’s happiness and peace. The object is for each child to become a source a peace and happiness for every living being. That is the whole aim of the school.
In this way, when the children have this great quality of a human mind, a good heart, they don’t give harm to others. All other living beings do not receive harm from them, and that absence of harm means they receive peace and happiness from those children. On top of this, the more the children develop, the more peace and happiness they bring to others. Others can receive the peace and happiness of this life from them, and the peace and happiness of future lives as well, up to the highest happiness: liberation from all suffering and its causes. That means the children can bring so much peace into this world, into other universes, in this and in future lives, by continually developing a good heart. Besides bringing peace and happiness to their own country, their own area, and own family, the children can bring great peace and happiness to other countries, areas, and families.
It is OK if there are parents who don’t have an interest in Buddhism and they want to take their children out of the school. You are trying to develop the rest of the children more deeply, and you couldn’t if those parents were blocking you. It would block the development of the children’s inner wisdom and good heart. If you explain it in this way, there should be no negative reaction due to a child leaving the school.
Alternatively, you could give less Buddhist instruction to those children whose parents are not Buddhist, and teach the rest in a fuller way. This would allow the other children to stay in the school.
If the objectives of the school are very clear, people will be happy to offer the school financial help.
