Invitations. Sending customized Hogwarts acceptance letters out will help to get kids excited about the wizard-world that awaits them, and making individual invitations is a relatively easy project that older kids can help with. Using a computer, type out the official letter Harry Potter received in book one, making only a few adjustments to the text and using a formal calligraphy style font - invitations can be printed on parchment style paper for an extra special effect. Here is an example.
of WITCHCRAFT and WIZARDRY
Headmaster: Albus Dumbledore
(Order of Merlin, First Class, Grand Sorc., Chf. Warlock,
Supreme Mugwump, International Confed. of Wizards)
Dear (name of guest),
We are pleased to inform you that you have been accepted as a guest at the Hogwarts School of Witchcraft and Wizardry birthday bash for (name of birthday boy/girl).
Please find enclosed a set of directions for meeting us at King's Cross Station Gate 9 ¾ (include directions to your house)
The celebration begins on (date of party) and will last approximately (number) hours. We await your owl by no later than (RSVP date).
(Parents or Host's name)
Decorations. It can be difficult to transform an outdoor summer birthday bash into a dark castle - so Hogwarts-themed colors should be used to dress up outdoor spaces. Hang crests for each of the four houses (Gryffindor, Ravenclaw, Hufflepuff and Slytherin), "potion filled" jars of candy or colored balloons and streamers.
Food. Instead of having a dessert table, set up Honeydukes Sweet Shop with homemade treats, chocolate frogs and Bertie Botts beans. Serving simple birthday fare (pizza, burgers and hot dogs) may be best, as the candy bar will likely be the focus of the event.
Games. When children arrive, have them grouped by the sorting hat, which will separate them into the four houses. Craft tables set up for decorating house banners and wands will help kids feel like they have entered into Hogwarts - just be sure to provide large paper sheets, wooden wands, paint, house-colored (red and gold, blue and bronze, yellow and black and green and silver) ribbon and other decorative items.
Hosting a Quidditch tournament (without flying of course) using brooms, a ball and two goals is a great way for kids to burn off energy and awarding Knuts, Sickles and Galleons to winning teams (and in slightly smaller quantities to losing teams) is a fun way to control the candy bar - with kids using the Wizard money to purchase items from the dessert shop.
Favors. Send kids home with items like colored bubbles, natural cotton bags filled with candy, fake black-rimmed glasses and customized birthday playing cards for magic trick practice.