2018-09-14 Update: 

Since it now been five years since the Computer Lab was operational this page is more archival than an up-to-date resource. We continued to help the Butterfly Children with their secondary school mathematics. We really like website that includes the K-12 common core math curriculum. It is possible to subscribe one month at a time. We have continued to use and recommend DragonBox Algebra.  

One of our readers Elliot also found this fun page that's been a great help to him as well - . It is also a curated list of mathematics software. He was thinking that it'd be a cool replacement for your broken link, "". It's too bad this link is no longer working because it was a favorite.

Crayon Physics Deluxe is a 2D physics puzzle/sandbox game, in which you get to experience what it would be like if your drawings would be magically transformed into real physical objects. Solve puzzles with your artistic vision and creative use of physics. 

TuxMath is an arcade game that helps kids practice their math facts.

TuxTyping is an educational typing tutor for kids starring Tux, the Linux penguin.

Faronics Deep Freeze Restores the computers to their previous configuration when rebooted. This means the children cannot harm or change the computers by pressing buttons. We just reboot them when they are finished and they are back to normal. This has eliminated maintenance from unintentional student error to nothing. We recommend this software for all children's or public computers.

Machinarium is a challenging puzzle-adventure game without language. It emphasizes reading and following instructions, completing tasks in sequence, and remembering information. This game has won international awards and is now available on the iPad  Machinarium

GCompris is a collection of 118 educational computer games for children. Free for most games, but a small donation unlocks all games.

Jeopardy Create Jeopardy games online and play them offline. All teams write down the answers and place them in the answer box before the timer expires. This free game is the best we have seen.

Nullpomino is a free Tetris Game

Cogs is the basic sliding block puzzle made interesting with pipes, steam, movement, and added dimensions.

Here again is the link for the Timez Attack addition/subtraction/multiplication/division game. 

Here is the link for Sokikom, the online math game that includes the mathematics core curriculum

ThinkFun makes challenging and creative games. These games are not computer games so we can play them if there is no electricity. By watching children play these games, you can actually watch them think!  ThinkFun  Educational Insights Castle is one of our favorites.

Mathematics Worksheets: I like the site: to print mathematics worksheets. The children enjoy these, perhaps because they are not used to working from worksheets like these. Their school textbooks have a few examples, so I think they need lots more practice. This site allows you to customize the worksheets. Here is a similar site:  Here is another website with pre-made worksheets. 

Mathlines: This game teaches 10's complement subtraction. It only takes a minute to learn. The players are rewarded with new levels of gameplay. We recommend this game to any student learning addition and subtraction.

Dragonbox: This game and others originate from at the University of Washington. Treefrog Treasure is a great game to begin with.