When? How did you pet them? What did they feel like? Was their skin soft or hard? Silky or rough? Did you smile? Did it look like it smiled? Write about it.
If you can’t think of another good story to write about, then here are a few ideas…
What did you do on you summer vacation?
If you could ride a dolphin, where would it take you?
If you were a dolphin, who would you take for a ride? Where would you take them?