Your mission

Zip the frog is the captain of a little yellow submarine, and the hatch is stuck shut with five locks. The pipes are tangled, the crates are flat, the twin subs need steering, and the windows are cracked. Put the clues together, work as a crew, and you will be back on the surface in no time.

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.