"Happy Sabbath!" is what we say because God's blessed the Sabbath Day!
https://www.sdahymnal.org/. Multiple resources here including Sabbath School lessons
https://www.hideitinyourheart.tv/. These are A Cappella Animated Scripture songs to hide in your heart. Great for kids of all ages!
thisisredz - YouTube This site is Donald's favorite resource for playing music during our worship services.