Updating.....collecting more intel....pondering.
The pressing and filtering of the oil has great Gethsemane story potential and theological significance. I see this as a Cooking Workshop in the Gethsemane rotation.
Lot of work for small but tasty and very memorable result. Needs the process refined and vetted for Sunday School use. It would be easy to just buy a $100 seed oil extraction press, but I'm on the hunt for a DIY solution.
This Jewish fellow's video has a very homemade process, that by my count, took him about 40 minutes. Unlike some, he includes water to hasten the oil separation. However, I think his pressing technique using other materials and much more weight. Wood blocks, for example. (I can imagine having kids sitting on top as the weight that presses).
Also found this Sesame Street video showing a Jewish kid making olive oil using a traditional stone press. He makes the oil for his Channukah lamp, the Festival of Lights.
"He who has clean hands and a pure heart."
Olive oil was also used as a cleansing product for skin and hair.
Kids make their own oil ("Castile") soap. Cold method. Science Workshop! (because you include lye as a cleansing agent). Original link no longer accessible, here is a replacement.
Note: Soap must cure for 4 to 6 weeks. Lots of videos with methods and recipes online.
Here is another website that walks you through their process, with photos.