You can download individual items from Seesaw, parents might want to download as they go, rather than waiting until the end of the year, teachers might want to save an artefact as an exemplar, or to share with other teachers.
Just click on the 3 dots, then choose Download Item.
If the item was an audio recording over an image, you will get two separate files, an audio file and the image, if you want them together the easiest way is probably to just make a screen recording... Or if you want to preserve the audio without room noise, screen record with Soundflower.