This is a good move but I don't agree due to sustainability. With lack of funds for the cultural sector, exhibits might deteriorate. At P150 for the working sector, P50 for students and free every Sundays, I think that's fair...
http://www.spot.ph/arts-culture/the-latest-arts-culture/66907/free-entrance-national-museum-20160701 Will post in a separate entry our day trip to the museum :)