The first necklace and bracelet looks like cultured freshwater pearls from China back when they were making button, egg, and potato shapes. There is no shell bead at the center so the pearls are 100% nacre.
The second necklace with round pearls could be cultured akoya pearls from Japan or could be more current cultured Chinese freshwater pearls, now that the Chinese are culturing with a round shell bead as a nucleus. To me they look like cultured Chinese freshwater pearls because of the milky luster and the silver clasp.
The third necklace is hard to tell because the photo is out of focus, but the beads look like mother of pearl, which would make them shell beads not pearls. Could you take another photo, please? And photograph on a white paper towel in natural light, but in the shade, not direct sunlight. That makes the pearls easier to see.
As far as what they're worth? Pre-owned pearls aren't worth much on the second hand market, especially freshwaters. If you're thinking of insurance value, they're also not worth much as these could be replaced fairly inexpensively. They're still very nice pearls, so wear them if you like them. Wear them with jeans, with dresses, or just because you like the feel of pearls against your skin. Wear them!