How do you get on the roof on Super Mario 64 ds?

Answer 1

collect all the stars inculdeing 25 secret stars, and the cannon that is covered by a grill in the castle grounds will be uncovered then you can blast to the top of the castle and there are some life mushrooms up there

Answer 2

Go upstairs, go to the right, and there will be a door with a star and no number on it. Go in the door, and head to the left. There will be a blank wall. Jump into the wall. Go to the right, avoiding the snowman and follow the wall until you reach an area with another snowman and a yellow box. Go over the hill, avoiding the spinning flower at the bottom. Jump onto one end of the "t", staying out of the water (It's very cold) and go to the other end of the "t". Wait for the spinning flower that's in the water to notice you. When it does, jump on its head and start spinning toward to brick wall. (This is somewhat tricky so you may have to restart if you don't get on the wall) Just slide down to to the yellow boxes. The shell is in the box on the right. Jump on it, and head back the way you came. Skate over the water, avoiding the "t" (if you hit the "t", your shell will collapse. Go past the "t" up the cliff, following the coins. Hop the fence, and crawl into the igloo.

Answer 3

Once you get all 120 stars, there will be a cannon that will be unlocked. Use that cannon to get to the roof of the castle. Once there you will get the red cap and the yoshi with it. He will reward you with the added triple jump special. (meaning you are succumb to lose life from high places) Hope this helps.