When my daughter was younger, she was in love with Rudolph. A party based on this character or reindeer themed party in general was perfect to plan since she has a December birthday.
For the party invitations, plates, napkins, etc., I found licensed items online. If I hadn't, I would have gone with red plates and napkins, and made something cute that was reindeer themed for my invitation.
Loving to dress up, we furnished everyone with a pair of costume reindeer antlers. A fun activity would be making your own with pipe cleaners and a head band.
We also (before the party) gave each person coming a "reindeer costume" to wear. T-shirts tie-dyed brown, a brown felt skirt, and brown tights. We even included black gloves and black socks (hooves).
For a December birthday party, a great party craft or party arrival activity is making Christmas ornament
For favors, toy reindeer items or glow in the dark or flashing items are a hit.
Some of the "reindeer games" we played were:
Older kids would enjoy an easy game of reindeer trivia.
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