Pros:
-fun
-a lot of leveling up possibility
-a lot of spells

Cons:
-very short no matter how much sidetracking you do (I did as much as possible)
-the prizes for collecting cards are crappy

Conclusion: definitely worth playing.

I have a GameBoy and I'm a GameBoy/ Harry Potter fan. It was a fun game with all the cool spells and creatures you fight. And collector's cards too. But if you're doing a MANDATORY magical encounter (like the Whomping Willow and the river troll), it's hard. And we don't see much Ron (but then he was dragged into the willow and didn't get to fight with Harry and Hermione after that) And it didn't stick to book as much as the movie. They took out the entire first 3 chapters of the book. They also didn't mention the Marauder's Map, Divination classes (but there was a mini-game),why he got a Firebolt (they don't say what happened to his Nimbus)or Hogsmeade visits. But don't think it's a bad game. Like I said, collecting Chocolate Frog cards were fun. And the Mini-games (especially Wizard Cracker Pop-it). I wonder if Goblet of Fire or Order of Phoenix will be as good.

PS: Eventhough they still don't explain what happened to Harry's Nimbus 2000 (like in the movie and book), it least he got it as a Christmas present unlike the movie where he gets it at the very end.

This is one of the hardest games I have ever played! Even for a Harry Potter game (which are usually fairly easy). The dementors don't do much though. What I really hate is that Harry has to go into the basement to get rat tonic for Ron's rat. Why can't Ron just get it himself? The game is really cool, though I wish you could hit Snape with that expelliarmus spell like Harry did in the movie.

After playing the first two Harry Potter Gameboy Advance games, this one was a bit of a disappointment. I don't like the staged fighting where you encounter the enemy and have to fight back and forth- they get a shot, you get a shot, they get a shot, you get a shot, until the hit points causes the other to be defeated. That's pretty much this entire game and it gets pretty annoying, especially once Ron and Hermione join in. Harry gives a hit, then Ron, then Hermione, then the first monster hits, second one, third one, and so on. Very repetitive. In my honest opinion the first two were a lot better and followed the story better.

I will say that the graphics were excellent on this game and overall it was moderately fun. I'm a huge Harry Potter fan so I can't dislike it too much! :)

Its great! Execpt for its hardness. I had to beat Crabbe and Goyle it was hard. It took 5 times for me to beat them. We finished the game after 2 months. The giant rat was hard too. The Buckbeak rescue and Sirius and Dementor reuscue was hard too.The best part is the MINI-GAMES!!!!!!!!!!!!They were fun expecially the pop one. The time when Harry and Ron find the Hippogriff book its south of the Library then turn right.I also liked Fred and George's Shop. Also when you find Mcgonagall Its hard.Snape's wasn't easy either you had to get a series of ingredients.And beat a river troll in the finding.It was HARD!!!!!!I had to beat it 10 times.It got very fustrating.Also the finding of Ron and the Shrieking Shack Was Hard!You had to beat a Forest troll on the way back from under the Whomping Willow.The Willow tree fight was hard too.Then the HARDEST of all was the encounter withe Lupin (in werewolf Shape).You had Buckbeak, Harry, Hermione. You NEED to GET FOLIO UNIVERSTITI cards FROM FRED AND GEORGE's SHOP!!!!!!!!Or you won't beat that werewolf. This GAME is GREAT!!!!!!I reccommend it.Last thing the minigames are (After you finish that level): Riding Buckbeak(at Hagrid's), Pop Wizard Crackers(Dumbledore's Wizard Crackers for Christmas), Boggart Spell(Lupin's Lesson), Patronus Spell(Harry's Lesson with Lupin).You need to fight The Monster Book of Monsters 4 times.One in the beginning ,two in the place where Malfoy hid Some books and 1 in Madam Pince's Library.Beware Skeletons come out of nowhere in the place that leads to the Shrieking Shack.Ther very tricky(Always say Lumos).
Before you rescue Ron you have to go into a place where the Waterfalls are.There is a switch hidden just find and press'a' or if that doesnot work try the up button then it will frezze Something then you keep trying to find switches until all of the small waterfall steps are frozen.I love this GAME!!!!!1!!!1!