Stop starvation using Rotten Flesh.

Construct a Dispenser.

Throw diamonds at another player.

Kill a creeper with arrows.

Turn wheat into bread.

Construct an Enchantment Table.

Feed a dolphin raw cod and have it lure you to treasure.

Craft and place a sign.

Catch and cook a fish!

Acquire diamonds with your iron tools.

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

Smelt an iron ingot.