My kids school does both Hannukah and Christmas(those two words are even on DD's spelling test

), but there really isn't a religious tone to it.
They learn the dreidel song and the light the menorah song in music as well as Jingle Bells and other non religious Christmas songs.
They have Christmas trees in the hallways and in art the kids all make ornaments, each grade has a theme, last year DD's class made Arthur ornaments, the year before they had a NYC tree and they made taxi ornaments.
There are colored pictures of menorahs and dreidels on the walls.
Their worksheets are Hannukah and Christmas and Kwanzaa related.
They also learn a little about Ramadan and Diwali. If kids celebrate something else, they are more than welcome to have their parents come in and tell all the other students about it.
I think it's terrific, they include everything so they don't have to exclude anything.
The kids really don't learn the religious aspect, instead they learn about the customs that go along with these events.