Objectives: Rescue 2 Citizens, Rescue all citizens, Collect all Coins
Reward: 13 Coins, 205SP
Grab the Zapper, and remove the Timber trapping the Civilian. Go inside that building and grab the Coin too. Now head to the right of the screen and build a bridge using the Timber you've just picked up.
Grab the coins from around this new island, and then free the chap inside (the door is round the back of the building). Go inside and collect the Coin, then bust out your Zapper again to remove the floor you're standing on. Underneath you'll find more Coins.
Exit this building then go north and lay timber to cross the next island so that you can reach more Coins.
Return to the starting area and create a bridge to the final island. This rescues the Civilians, and after you've grabbed the final Coins there you'll have mastered it too.