P.S. And here's one that I used in college to help me remember the "special plurals" for the names of baby animals -- obviously spoofing the Gershwin song that goes "po-TAY-to, po-TAH-to, to-MAY-to, to-MAH-to..."

"Слонёнок, слонЯта!
Слонёнка, слонЯт!
Let's call the whole thing off!"

This shows the nom. sing., nom. pl., gen. sing., and gen. pl. for "baby elephant". There was really no point in continuing with the other cases, because by the time I had to learn the special forms for baby animals, I already knew the general declension paradigm for masculine animate nouns. So learning just the nominative and genitive in the singular and plural is really enough.