Star 1: The Galaxy's Greatest Wave Difficulty: 9/10
Bah, this one is very challenging, though not the hardest. You'll probably lose a lot of lives attempting to beat this level, but thankfully you can take your time. The coach penguin at the beginning says you'll get your reward if you manage to complete this stage in 3:00.00, and it should take you no longer than 1:30.00.
Right away you'll see that this stage will be hard. It's narrow and there are many of hard turns. Thankfully there are a copious amount of 1-up Mushrooms on the way, but just make sure you don't die trying to get them. Don't go too fast, as it'll probably mess you up at the end. Keep the Wii remote steady, and don't get too nervous. Also, don't be afraid of the large loop, as it's no different than going straight, and probably easier than taking the tight turns.