Nice challenge! Sixteen images sure makes for extending that muscle memory
Food (Beer, Burger, Paper Coffee Cup, Coffee Mug)
Animals (Cat, Squirrel, Penguin)
Human Emojis (Fist bump, Two thumbs up, Ninja, Rage)
Weather (Sun, Storm, Star) (In hindsight, a darker background on the star and storm cloud would make them pop)
Miscellaneous (Grocery Bag, Music Note)
Thanks for the challenge! @Michael_Bridges!