Do you mean physical activities?  What about apple bobbing for Hallowe'en?  Possibly carving pumpkins (depending on health and safety - knives) or cutting out pumpkin faces from orange card.  This way you can also teach them the more pagan meanings behind the traditions, without pushing the issue.

For Christmas you can make cards, decorate a Yule log, make snowmen from toilet rolls and cotton wool, learn a carol or two or make mince pies (if you can get hold of the mince meat).

I have to say I know nothing about Kwanza or Hannukah (I'm probably butchering the spelling too).  We never learned anything about them when I was in school.

Whenever I want ideas of things to do for my son I look up homeschooling info on the net, you can get loads of ideas from those.  Try the Crayola website, they have stuff to print off and craft ideas on there.

I should have a few more sites bookmarked somewhere (my favourites folder would look like a family tree going back hundreds of years if it were diagrammed... ) if you want them?