Video camera for online course creation
I would whole-heartedly recommend the Panasonic HC-WX970K 4K Ultra HD Camcorder for this purpose:


When shooting 4K video, you can shoot wide enough to capture unexpected or exceptional things that happen outside your normal framing area while still having plenty of resolution for an excellent 1080p video.
It happily shoots exceptional quality 1080p120, which is true slo-mo.
It is small so it can fit on a bench without great disruption.
It has built-in ND filters, so you can have your bench inside or outside and still use sane aperture and shutter speed combinations.
It costs less than $800.


n.b.  If you shoot at 4K with a consumer camcorder, chances are you'll be shooting at 24fps or 30fps, which means there will be motion blur.  But if you can tolerate that, you'll get gorgeous still shots you can crop to whatever size you like.  If you shoot at 1080p60, you will greatly limit motion blur, but you will also be more constrained in how much you can crop, and how good the image looks when frozen as part of a diagram.  But a 4K camera such as the above will allow you to experiment and find the best of both worlds.