Scratch Jr is an app on iPad and Android tablets, and is ideal for introducing basic programming concepts to non- or early readers. It is a good stepping stone to Scratch, using similar commands, but with images instead of text on each block.
For schools without tablets, there is a desktop version and a Chromebook version. Neither of these are official products, but they work exactly the same.
As with Scratch, introduce the code blocks individually away from the computer – pupils could act out or model what happens. Provide tinker time with the app, and scaffold learning by providing a limited set of commands to use in a project. Encourage pupils to plan out programs on paper first, to help identify any issues and provide greater focus. You can also provide code for pupils to investigate, debug and predict the outcome of – following the PRIMM model.