There are many ideas out there for praying the O Antiphons that begin today, including the novena I just posted. I have very simple plans for us this year.
We will pray the Antiphons with our Advent Wreath in the evenings as they are prayed in the Divine Office. We say the Antiphon, pray the Magnificat, and repeat the Antiphon. Before or after dinner, depending on timing, I'll have the children color the images here to hang as decorations. That's it.
If you want more wonderful, creative ideas, these sites are amazing!
Detailed Explanation of Antiphons - http://www.fisheaters.com/customsadvent10.html
Jessica's Fun Plans - http://showerofroses.blogspot.com/2009/12/celebrating-o-antiphons-our-plans-for.html
Charlotte's Fun Adaptations - http://tiredtwang.blogspot.com/2009/12/o-antiphon-activities.html
Jessica's Amazing Antiphon House - http://showerofroses.blogspot.com/2009/12/o-antiphon-house.html
Mary Ellen's Links to More Amazing Ideas - http://maryellenb.typepad.com/o_night_divine/celebrate-with-o-antiphons.html