We began our Hogwarts adventure with the invitations.  I wrote the invitations in green ink on parchment paper and copied the letter that Harry Potter received in the first book almost verbatim. I added one line and it was "First year students will the additional pleasure of celebrating Miss Meghan \*\*\*\*'s 8th birthday in the great hall imediately following the sorting ceremony.  We await your owl now later than September ##." I even sealed the envelopes with wax. My child invited everyone in her class and then some; so I got her teacher's permission to shove the letters under the classroom door just before the end of the school day.  The teacher walked over to the door and looked puzzeled and wondered out loud what was going on.  She even opened the door and said, "There's an owl out here!" She let the children open their invitations and some thought they really received Hogwarts acceptence letters. My mother and I sewed 28 black robes for the first years. We arranged to have the party in the fellowship hall at our church, it looks like a castle on the outside and had a large rectanglar room that kind of resembled the great hall in the Potter movies. I had adult friends dress up as Hagrid, Professors Quirrell and Trelawney, Madame Hooch, and Professor Snape. My husband was Professor Dumbledore and I was Professor McGonagall.  We had a sign at the church entrance that read "Platform 9 and 3/4" and Hagrid greeted each child as they got out of their car. We had the movie soundtract playing in the background and Hagrid helped each guest into their robe.  I had older cousins and neighbors pretend to be second year, third year, fourth year, etc. students.  When the last guest arrived, the professors and older students went into Hogwarts (the church) one way while Hagrid took the first years and led them the long way around the "castle" and into the great hall. We decorated the great hall with 4 long rows of tables and on each table we had streamers with each of the House colors and lots and lots of candlesticks with candles lit.  At the head of each table was an older child who acted as a Prefect for that house.  The other older children helped to fill in the tables and clap loudly when each child was sorted into their house.  The first years came in and Professor McGonagall took a large roll of parchment (long roll of paper on a paper towel cylinder) and called each child one by one to be sorted.  The child came up to the front of the room and sat in a seat and put the large sorting hat that I made out of poster board and black felt on their head. My husband hid behind some furniture and used the churches small PA system to talk for the sorting hat.  I had a script for him to follow so that he said something special about each child. For example, the "hat" would say "Ah yes, an intelligent child, good baseball player, loyal to his friends . . . GRYFFINDOR."  When the sorting hat called out which house the child was to join, the older students clapped and yelled for each child so that they felt special and wanted.  The "Prefects" of each house took a pin that we had made, consisting of 2 colored ribbons (whatever the house colors were . . red/yellow, green/silver, black/yellow, and blue/black) tied together on a saftey pin. The Prefect pinned the ribbon on the newest house member.  When all of the students had been sorted, Professor Dumbledore welcome everyone and we ate our pizza with pumpkin juice (orange soda in clear glass pitchers with a lable).  While we were all seated, we had our cake (decorated with the Hogwarts crest) and ice cream. The adults who were acting as professors ate at the head table.  After the meal, I called for each house to line up behind their Prefects to go to Potions class.  Professor Snape greeted the students in the laboratory (which was a large kitchen off the great room.) We had black caldrens (plastic halloween ones), wands (small sticks we found on the ground) and ingredients ready for each student.  The students had to mix frog eyes (moth balls) with dragon's spit (vinegar.) Then Professor Snape had them say an incantation and wave their wands before adding the final ingrediant, powder ground up from a unicorn's horn(baking soda.) The potion fizzled the balls popped up and the students squealled. After this lesson, the students joined Madame Hooch for a flying lesson.  We had brooms on the floor each one's handle we labled with a gold pen "comet," "Cleansweep Five", or "Nimbus 2000" and it was funny to see all the students in their black robes saying "up" and trying to get their brooms to move.  Madame Hooch told the students that some first years did not have enough magical training to make the brooms move so they would have to lift them up like muggles. After a brief flying lesson, Madame Hooch had the Gryffindores play Slytherin in Quidditch.  I had one adult on each side of the room hold a hula hoop and students mounted their brooms and threw the quaffle ball to one another to try to score.  Each team had assigned who were going to be the beaters, the chasers and the keeper and each team also chose one seeker.  They had to stay on their brooms and throw the Quaffle to a teammate who would try to throw the quaffle ball throught the hoop.  The quaffle was dropped and intercepted many times.  We let the game go on for 3 or 4 minutes and then I threw the snitch (a small yellow bouncy ball) onto the field and the seekers chased after it. The team who's seeker got the snitch won.  Next, we let Ravenclaw play Hufflepuff the same way. After the Quidditch matches, we went back to the Great Hall to open presents.  Afterwards, Professor McGonagall let the students take a "trip" on their brooms to Hogsmeade village to visit the candy shop where students could find all Harry Potter's favorite candy (chocolate frogs, bertie bot's every flavor beans, pumpkin pops, etc.) The birthday girl just happened to have a pocketfull of wizard money which she shared so everyone could "buy" the candy. The students posed for a class picture and the school day was over.  I let each child keep their robe, their caldren, and their broom and; of course, the candy the bought. It was some party and my daughter's friends are still talking about it.  I can't wait to do it again for my son's birthday when he is old enough to enjoy it. FYI: We bought the black plastic caldrens and broom sticks for a dollar apiece at the local dollar store. My daughter's birthday was in September so it was the right season for finding this stuff.   My mother and I found at Walmart a simple robe pattern and inexpensive black cotton for the robes. I sewed 18 robes in one day because it was so simple to do. We bought bag candy and sorted some into small ziplock bags for the candy at the candy shop and labled each bag with the appropriate name.