If you’re wondering, Why recorders? — there are three reasons:

• They’re portable.
• Recorders in decent enough quality can be cheaply produced, so even low-income children get to play one. Compare that with a guitar where 30$ gets you a piece of wood that detunes as soon as you lay eyes on it. Not great for practicing.
• Recorders have an easily memorizable fingering scheme that allows you to quickly pick up the C Major scale. Compare this with a guitar where you need to remember for each string individually which frets have the notes of the scale.