kids love to learn about animals but i think parents should save some for later. finding out about giraffes when you see one for the first time at age 17 would hit so hard

"yeah dude they're pretty cool i guess, it's just like a really tall horse"

"what the fuck is a horse???"

Additional modifier: tell them that some of the conceptually more out there animals (kangaroos, penguins, the aforementioned giraffes) went extinct with the dinosaurs.

Now, some may call this "gaslighting" but imagine the look in your hypothetical child's eyes when they go to the zoo and see a creature they've been told is dead for hundreds of thousands of years. Pure magic, like they're seeing a dragon or a unicorn. They won't ever trust you again but parenting is a series of compromises.