I will think a bit about projects... but as for your student, I might have a little insight.
It can be very hard for gifted children to find that not everything is easy and not everything is perfect, sometimes not the first time and sometimes not the 10th time. Learning that is a life skill in itself. I remember in 10th grade one student bursting into tears (in an honors class) because she got a B on an assignment and it was the first B she'd ever gotten. She was not prepared, there is still time for yours!
Don't know if it would fill the time slots, but maybe first making stuffed animals and then making clothing for them would be fun. Obviously it would be easiest if you chose a project designed for that sort of thing instead of having to create patterns, but making basic sack type dresses or whatever without a pattern cold work too. It would be a way to learn about sewing on fancy materials and trying out different techniques like ruffles or tucks.
One of my sayings is "fabric is treacherous", one of the reasons I like working with 100% cottons. When discussing projects and doing the clothing you need to warn about slippage and proper pinning and all sorts of things. If it was me, I'd probably do a quick couple of videos and check some of my old techniques for dealing with velvet and satin, and maybe do a few tests on your sewing machine to figure out the various foot and thread tensions and such.