Scratch Junior is a developmentally appropriate programming language for children ages five through seven. It is available through the App Store and Google Play for free. Furthermore, if you don’t have an iPad or Android based tablet, you can emulate a full Android OS for mobile applications using the Andy Android Emulator for PC and Mac. It’s a fully functional, independent Android operating system that runs as an application in Windows or Mac, and also free. There is no real configuration needed, when Andy is launched, open the Google Play Store and find ScratchJr.
The official Scratch Jr website has a learning space where you can access an interface guide, paint editor guide, block descriptions and tips and hints. It also has a teaching space, providing you a quick way to learn how to do new things with Scratch Jr. However, if you are looking for more detailed step by step lesson plans you can download this PDF for free. It contains lesson plans (or modules) for creating an interactive collage, an interactive story and a game using Scratch Jr. Each module contains a summary, objectives and lesson steps with suggested time allocation.