This game was interesting to play. I love the lightness of the Lego games. No matter how serious the game is supposed to be, some lego person's head pops off or something equally amusing happens to lighten the mood.
What I liked in particular to this game, was how interactive the player has to be. It's not just button pressing. In fact, you really only use your directional pad in this game, everything else is pretty much the stylus. Whether you have to draw a spell to cast it, or trace the cogs to open something, or play some simply game of memory, you have to be paying attention and have your stylus in hand. This fact made the game fun and way more interesting than most other games I've played. I also liked how to collect all the things needed to "master" a level you had to play as characters other than Harry, Hermoine, and Ron. There are instances where the player will need to be a villain to accomplish something.
I wouldn't suggest this game to anyone without the patience to remember the spells, the higher in level you go, the faster you have to draw the casting designs, which can be tedious if you're in a fight.
All in all, this is a fun game, and even with going back to previous years and levels over and over to make sure I'd gotten True Wizard, all the golden hats, and all the cards in each stage, it took me less than a month to beat it with only playing an hour or two a day.