This game will provide lots of fun and high levels of motivation that are sure to lead to learning the terms for unusual plurals. There are two sets with 45 cards in each set. That's 22 pairs and a DONKEY Card that gives the game its appeal.

The words I have used are:

Set 1: loaf/loaves, thief/thieves, goose/geese, wife/wives, knife/knives, mouse/mice, louse/lice, child/children, elf/elves, foot/feet, woman/women, man/men, tooth/teeth, leaf/leaves, sheep/sheep, calf/calves, half/halves, life/lives, that/those, this/these, person/people, die/dice

Set 2: medium/media, index/indices or indexes, wolf/wolves, shelf/shelves, scarf/scarves, radius/radii, cactus/cacti, fungus/fungi, self/selves, axis/axes, basis/bases, analysis/analyses, dwarf/dwarves, hoof/hooves, wharf/wharves, platypus/platypi or platypuses, ox/oxen, scissors/scissors, paralysis/paralyses, oasis/oases, nucleus/nuclei, crisis/crises

Reference books give conflicting answers for the plural of platypus. If you wish to leave it out it will not affect the game.