Kodu Game Lab - Kodu lets kids create games on the PC and XBox via a simple visual programming language.
RPG Maker - Make your own PC game with RPG Maker. Our easy to use tools are simple enough for a child, and powerful enough for a developer. Try it free today!
Ceilfire - Ceilfire is an online game maker for creating HTML5 games and sharing game assets. Make play and share games directly in your browser! Make Your Own Game!
Flowlab - Flowlab is an online game creator. Make your own games to share with friends.
Godot Engine - Feature-packed 2D and 3D open source game engine.
Wick Editor - The Internet's free and open-source creation toolkit.