Communication is important. When one does not understand a culture or religion, there is a tendency of mistrust and misunderstanding. It will be good to share with your parents what you plan to learn or have learnt from the Dharma. Be careful though, not to impose your ideas on others when you are sharing information with them. You may also want to invite your parents to attend Dharma events with you, so that they are aware of what you are involved in. Let them know where you are going, what you do in the Dharma centre, what you learn, and who your Dharma teachers and friends are. They will feel more at ease if they are informed and know what you are doing. The best and most effective way to convince your parents is through your actions and behaviour. If your parents see a change for the better in you, they will certainly allow you to go the Dharma centre.
I once had a student in Australia, a divorcee who used to have problems with her children. After coming to the Dharma centre, learning the Dharma and applying it in her life, her children noticed a positive change in their mother. Then came a period when she got too busy to go to the Dharma centre and started becoming cranky and reverting to her old behaviour. Her children were the ones who reminded her to go back to the Dharma centre.