The BBC Micro:bit is already super kid friendly, and can do servos and audio. You can program it using their own scratch-like language "MakeCode", or you can us

The BBC Micro:bit is already super kid friendly, and can do servos and audio. You can program it using their own scratch-like language "MakeCode", or you can use python. They have a web-based editor for both. And that web based thing also includes an emulated board, so you can try it even if you don't own a board. https://microbit.org/ https://microbit.org/ You can also buy kits that come with a load of sensors and nicely printed manuals, colour coded interface pcbs, and sensors with keyways so you can't get the connection wrong. They also include some extra "blocks" for the scratch-like language so you can really easily use them. Those are a bit pricey. Here's one example for £40 (which weirdly doesn't include the BBC Micro:Bit itself). https://coolcomponents.co.uk/products/smart-home-kit-for-bbc-micro-bit-micro-bit-not-included?variant=13659302068285&utm_medium=cpc&utm_source=google&utm_campaign=Google%20Shopping&gclid=CjwKCAjw2dD7BRASEiwAWCtCb8Cz06kJZjLqGXyBLY5Ssta-5sS-u20_6cGJQaOiIUDs8Hm11VvijBoC9EQQAvD_BwE https://coolcomponents.co.uk/products/smart-home-kit-for-bbc... You don't need to spend anywhere near that much though. You can buy a micro:bit and then get a kit of transducers from Aliexpress.