The Raspberry Pi Pico has opened the door to young experimenters thanks to the MMBasic programming language from Geoff Graham. There are several excellent videos that explain the setup and operation. The Pico is actually available for $4. The software and manual (PDF) are free to download. It is super easy to get started - 5 minutes and you're writing software that can solve problems and control I/O.
PicoMite: Running BASIC on a Raspberry Pi Pico
https://www.youtube.com/watch?v=Cxmjy1nz6MM
PicoMiteVGA Raspberry Pi Pico Running BASIC on VGA
https://www.youtube.com/watch?v=gIK1ujslHHI
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