Originally a practitioner of provincial Art Nouveau in Samara and Moscow, he later joined the camp of rationalists and focused on perfecting school and museum designs.

In 1905 Zelenko joined educators Stanislav Shatsky and Louise Shleger on their Summer Labor Commune project in Shchyolkovo, then on Russia's first club for the children.

Funded by industrialist Nikolay Krotov,[3] Zelenko designed and built extant Communal Club for the Children in Moscow (completed 1907, Vadkovsky Lane, 5).

Vadkovsky lane house integrated Settlement program with traditional kindergarten for working families and a two-year junior school.

After the Russian Revolution of 1917, and until his death in 1953, Zelenko worked in various Soviet educational institutions, notably in setting architectural standards for schools and kindergartens.