My daughter turned six this December so we decided on a snowflake theme. We used snowflake stickers to decorate invitations.  The decorations were very simple because I had out the Christmas decorations.  We also made a big snowman in the front yard holding a sign that said, "Happy Birthday Name". Inside I used a large box draped with a white sheet to make a simple igloo.  Besides the Christmas decorations I also had dancing snowballs set throughout the house.  To make these, fill a small jar with water, add blue food coloring 1 tsp each citric acid and baking soda and 3 or 4 mothballs.  When the children arrived they made beaded snowflakes. They all turned out so nice and the childrens all seemed to enjoy this.  I had hidden cotton balls all over the house. The next activity was to hunt for these. I divided the kids into a penquin team and a polar bear team. Only the captain of each team was aloud to collect the cotton balls.  If someone on their team found a cotton ball they were to act like a penquin or a polar bear and the captain would know to come running.  When most of the cotton balls were found we put them all on a white garbage bag, each held a corner and threw them up into the air to creat a snowstorm. We then blindfolded the kids and had them crawl around, bumping into each other, trying to pick them all up.  It was so funny to watch! Next we put all the cottonballs into a treasure chest I have and the children put on a blindfold and mittens and each took turns choosing a toy from the treasure box by feeling through the cotton balls for the one they thought they would like.  For a birthday cake we just had snowman cupcakes. While these and the drinks were being served we made ice cream by filling a liter zip-lock bag with snow, adding 6 TBSP salt and having each child squish it. Then we filled a smaller ziplock bag with 1/2 cup cream, 1 TBSP sugar and 1 tsp sugar. This goes inside the snow bag and the kids all get another chance to squish it.  This makes enough ice cream for each to have a little taste.  They were all impressed. After cake we had the snow-angle ball. They got ready by making themselves a snow headband, then we used makeup to give each a sparkly snowflake on their cheeks. They dressed up in playclothes (mostly white dresses) in the igloo. At the ball we played freeze - snowball dancing.  The snowballs were white paperplates they could step on and glide across the livingroom floor.  When the music stopped they would have to freeze.  We also had large marshmellows tied on string one person held the end of the string in their mouth and tried to swing the marshmellow into the mouth of their partner. At the ball there was a veriety of food: fruit and veggie tray, pop corn balls, meat, cheese and cracker tray candy bowls, chicken fingers with dipping sauce...  The last activity was a snowball fight using wadded up newspaper. This is all we had time for although I had lots of other activities planned.  It was quite cold outside so we did only inside things. They went home with their crafts, and a goodie bag full of snowflake items.  Also they were so intriqued with the dancing snowballs I showed them how they were made and we made sure each child took home a jar of dancing snowballs too.