Every Passover Bank Hapoalim sponsors free entrance to over 40 museums, national parks, and heritage sites in Israel as part of their social program. Also see “Things to do in Israel during Passover”.
http://www.touristisrael.com/free-passover-museums-sites-2012/5802/
http://www.touristisrael.com/passover-in-israel-april-6-13-2012/5560/