*A note to youngsters: Before you play, you should be confortable with the four basic arithmetic operations, the order of operations, and negative numbers. If any of those are unfamiliar to you, just stay in school and you'll learn them eventually. Or talk to your parents and they may be able to explain them to you.*

This is an example puzzle:

1234

Mathematical signs can be placed in each box. Solve the puzzle by placing exactly one equals sign and any other signs needed to write a true equation. Here's one solution for the example puzzle:

1234

You don't have to fill each box. If you don't fill a box, the digits on either side of the box will be considered to be part of the same number. Here's another solution for the example puzzle:

1234

As you can see, that puzzle has multiple solutions. Many puzzles do. Part of the challenge is finding as many of them as you can!

27 puzzles are available. Try them in any order you like!

Place a sign by selecting one from the left menu, then clicking on the box to put it in. Use "Erase" to empty a box. Click "Check" to submit your solution, and click "Menu" to go to another puzzle.

For the first valid solution you find for a puzzle, you get 30 points. Each additional solution for the same puzzle earns you another 20 points for each one. Earning lots of points can get you new ranks. Move your cursor to "Rank Chart" to see how many points you need.

If you like, you can play the game using the keyboard. You can switch between keyboard and mouse any time without having to change any settings.

When you see the Begin button on the first screen, press the space bar to proceed to puzzle selection. Choose a puzzle using the arrow keys and press the space bar to confirm your choice.

When solving a puzzle, use the up and down keys to choose a sign, and the left and right keys to move between the different boxes and the Check button. Press the space bar to enter the chosen sign or submit your solution. Press M to return to the puzzle menu.

"Help" and "Quit" are ordinary links, so choose them the same way you'd choose a link on an ordinary Web page (typically by using Tab and Enter).

Hit R any time to show or hide the rank chart. Hit Esc to close this help screen. The Enter key does the same things the space bar does.