GCompris is an educational software suite with numerous activities for children aged 2 to 10. Some of the activities are game-orientated, but nonetheless still educational. These include computer discovery (keyboard, mouse, different mouse gestures), algebra (table memory, enumeration, double entry table, mirror image), science (the canal lock, the water cycle, the submarine, electric simulation), geography (place the country on the map), games (chess, memory, connect 4, oware, sudoku), reading practice, and others (learn to tell time, puzzles of famous paintings, vector drawing, cartoon making, etc.). It currently offers in excess of 100 activities, and more are being developed.
KaPooka is an animated logic game for SDL. It's kind of a cross between Sokoban and Pengo with regards to gameplay. You move your red blobby around, pushing the green blobbies out of the way and finding the exit. The game currently consists of 30 levels. Anyone that feels like contributing other levels is most welcome.
XWelltris is a 2.5D Tetris-like game. Imagine that you are looking into a glass from the top. You see four walls and the bottom. Flat 2D figures fall down from the walls one by one. You can move these figures from one wall to another or rotate them. If the figure leaves the wall, then it moves to the bottom while another figure is pushed. You need to form full rows or columns on the bottom. When you form such row it disappears and you receive additional empty space on the bottom and your score increases. Extra points are earned by making more rows disappear at the same time. If you can't place a whole figure on the bottom, then it stays on the wall and you can't place figures on that wall for a while.