Thirtieth patriotic education bases, libraries, youth palaces and children's activity centers shall be open to minors free of charge; Museums, memorial halls, science and technology museums, exhibition halls, art galleries, cultural centers, theaters, stadiums, zoos, parks and other places shall be open to minors free of charge or at preferential rates in accordance with relevant regulations.

Judging from the "should" in the clause, it should be understood as a general provision. If there is no such word, it is mandatory.