Pilea peperomioides
Round, coin-shaped leaves on thin stems, easily propagated from the baby plantlets it sends up around its base.
Drooping, curling leaves are usually a watering issue in either direction — check soil moisture before assuming it needs more water. Leggy stems reaching to one side mean the plant needs to be rotated toward its light source more often.
Remove the small plantlets that sprout from the base or roots once they have a few leaves, and pot them individually — they typically already have small roots attached.
Repot every 1-2 years as offsets crowd the base — dividing and repotting the plantlets at the same time is an easy way to multiply your collection.