Click nucleic acid monomers and polymers containing such monomers are disclosed. The click nucleic acid monomers include an optionally protected thiol moiety, an optionally protected thiol-click acceptor moiety, and an optionally protected nucleobase (NB), which in some examples is an A, G, T, U, or C nucleobase. In some examples, the click nucleic acid monomer includes a N-vinyl thiol acetamide (VTA) backbone. In other examples the click nucleic acid monomer includes a N-vinyl thiol ethylamine (VTE) backbone. Methods of using such polymers, for example in place of naturally occurring nucleic acid polymer applications, such as DNA or RNA, and synthetic nucleic acid polymer applications, such as PNA or morpholino nucleic acids, are also disclosed.