Your mission

Zip the frog has traveled all over the world, and his trunk of postcards is locked five ways. A LANDMARK is a famous place that people travel a long way to see. Some landmarks are buildings, like a tower or a temple. Some were built thousands of years ago, and some are much newer. Every landmark tells you something about the people who made it.

How to crack a lock

  • Pick any lock from the menu at the top. You can solve them in any order.
  • Read every clue before you start. One clue alone is never enough.
  • Use scratch paper. Draw pictures, make lists, and cross things out.
  • Tap the buttons to build your answer. Then press "Try the lock".
  • A lock will not tell you which part is wrong, so be sure before you try.

My badges

Teacher note

Teachers: type the password to see the answer key.