Rhacophoridae
Most of the species are arboreal. This may include reproducing in trees. Mating frogs, while in amplexus, hold onto a branch, and beat their legs to form a foam. The eggs are laid in the foam.  They are then covered with seminal fluid. Then the foam hardens into a protective casing. In some species, this is done in a large group. The foam is laid above a water source, so the tadpoles fall into the water once they hatch.