I am not a homeschooler (except for myself!) but audio can a blessing. I have collected thousands of edifying sermons and testimonies, and being a boomer, and with society going digital, we always had FM radios. And so I placed about 14,00 of them on a USB powered SSD, and use a free audio player like JetAudio basic to random play the whole "disk," and plug in a USB powered FM transmitter into the audio port, and set it to broadcast at a empty spot on FM band (88.7 here). Thus in every room we want we can hear edifying messages and testimonies.
I was also able to get a portable FM radio so I can hear it while outside in the garden and working on bikes on the sidewalk, where customers (though all labor is free in this Christian ministry, but I ask them to cover cost for part, which I pray and seek to get the lowest price for, and all items i linked to above, which I bought, are under $20 ), thanks and glory be to God.
I know smartphones can do playlists, but mine are from my own collection. I am listening to this powerful sermon right now (though on my end it is from my FM radio).
I am going to share this post with others on my apologetics ping list as they may be interested.
I would be interested to know of works of Christian Apologetics published prior to 1930 (now public domain) that you would recommend, from your book collection.