Does opening the curtains and letting the sunlight stream in help prevent mold from growing in your bedroom?

Yes,you can't beat fresh Air and sunshine.Mold likes dark and damp not necessarily wet places to grow.Its all about tightness in a home now a days and I truly believe that is not always a good thing.If you have a mold problem tackle it before it can get out of hand.Bleach and water works fine.Blessings!

Yes, it definitely helps. Stagnant air is as bad as stagnant water. Good air circulation can reduce the chances of indoor mold growth. You need to regulate the indoor humidity as well. Maintain the humidity level at or below 50% can drastically reduce mold growth.

yes it does coz moisture is needed for mould to grow

it will help ...but nowhere near as much as opening the window ...you must keep an airflow