Start with a game plan -- are you going to watch all seven movies or will you just watch the most recent ones to get caught up? If you are dedicated to watching them all, consider splitting this event into two nights to squeeze them all in. Remember to keep the number of muggles limited to the space that you have in your home -- since this is going to be a long party, you want everyone to have enough room to be comfortable.
Send a fun and interesting invite -- a regular invite just won't do for this get-together! Record a howler, like parents used to send to their kids at Hogwarts -- you should be able to record yourself screaming the details of the invitation on your phone (voice or video), then email it to your guests. Bonus points for dressing up like Mrs. Weasley -- or even better, dress up one of your kids as Mrs. Weasley and have them scream the howler invite!
To keep this marathon going, you're going to need a lot of food! Start with butterbeer, which you can serve in fun freezer mugs to keep cold. Mrs. Weasley's rock cakes are a great option -- you can make a simple scone recipe easily and then addgoodies such as dried fruit or chocolate chips to make them tasty. Don't forget boxes of the Bertie Bott's Every Flavor Beans from Jelly Belly (which includes flavors such as vomit!) -- perfect for snacking on during the movies. The kids will love helping you make these owl cupcakes, in honor of Harry's beloved owl Hedwig -- or make Harry's favorite dessert, treacle tart.
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Decorating your house for the party will be fun, with so many creative options from the books and movies to pull from! Start at your front door with a sign for Platform 9-3/4, just like the one Harry and his friends used to find the train to Hogwarts. Inside, consider making banners for each of the Hogwarts houses to hang throughout the house, paint or print out old pictures in gaudy frames like the ones in Hogwarts where you had to give your password to get into your respective house, and don't forget a recording of a Moaning Myrtle for your bathroom!
Consider if you'd like this to be a costume party. Since it will most likely run into the night, make a robe the required attire, just like Harry and his friends at Hogwarts wore to class every day. When they get to the party, have supplies so guests can make their own house crest to pin to their robe -- you can have standards pre-made for all the houses of Hogwards (Gryffindor, Hufflepuff, Ravenclaw and Slytherin) or let each wizard create their own.
Although the movies will be the highlight of the party, plan some activities for in between movies to keep the energy up! Have a potions class set up in your kitchen with fun ingredients for kids to mix up to create their own crazy concoctions -- put tasty sweet ingredients in baby-food jars and then label them with creative names. You can also have a Sorting Hat ceremony, where each person has to take their turn under the crazy sorting hat to be placed in a Hogwarts house. A wand-making craft would also be fun -- have each person bring something from home as their wand or pick up some small dowels from the hardware store and let each person go to town decorating them with paint, glitter, yarn and ribbons to attach to the ends. Go wild with ideas and have each person create their own spell!
During the movie itself, keep your muggles engaged with some trivia -- print out quizzes for each movie with questions about details in the movie, such as what kind of feather is in Harry's wand or the name of the town where Harry's aunt and uncle live. You can find tons of questions and trivia online. Collect all of the cards at the end of the movie and award a prize to the winner.
Whether you choose to keep this movie marathon simple or go all-out, have a great time spending time with family and friends to celebrate Harry Potter and the Deathly Hallows Part 2, which premieres in the US on Friday, July 15, 2011.
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