These thematic pictures of календарь are analogous to a visual dictionary. The theme "календарь" splits into several parts. For children, especially toddlers from 1 to 5 years old, it is better to divide the sets of cards over several days, or even weeks, so the information is absorbed better. Especially it is true if you are using flashcards to learn the ukrainian language, which is not your native language.
To expand your ukrainian language vocabulary on the "календарь" topic, flashcards games are the best way: