Craft and place a sign.

Deal nine hearts of damage in a single hit.

Construct an Enchantment Table.

Destroy a Ghast with a fireball.

Use a saddle to ride a pig, then have the pig get hurt from fall damage while riding it.

Kill a skeleton with an arrow from more than 50 meters.

Construct a Nether Portal.

Construct a better pickaxe.

Construct a furnace out of eight cobblestone blocks.

Punch a tree until the block of wood pops out.

Turn wheat into bread.

Wear a full suit of Iron armour.

Construct one type of each tool (one pickaxe, one spade, one axe and one hoe).