The shop
Keep the episodes for good.
Some families would rather simply have the audio: files that live on your own device, work in a car stereo or an old MP3 player, and never depend on an app, an account, or a signal. Those are available in the shop.
Individual episodes are $2.99. The Starter Collection gathers ten of them, including Volcanoes, Thunder & Lightning, Shooting Stars, and Sleep, for $14.99.
Not every episode is in the shop yet, and newer ones usually take a while to arrive. If the one you are looking for is missing, tell me which one and I will get it added.
Buying is never required. Every episode is free to stream, always, everywhere.