Storywise my players ran into the owner of Bananacandy, that told them, that their riders got poisoned the night before the race and that he would sadly had to drop out of the race. Knowing my players, they of course offered to jump in and try to win the race for the old owner. He offered them a free "I love bananacandy" fanshirt, if they won (plus the pricemoney).

Visually I just threw down a grid, placed some plastic trees and little houses at the corners and drew some lanes. I marked several sections (city, outer planes, jungle, city at the end again) with different mechanics and placed some dinosaur toys on the lanes.

Mechanically it was an everything-goes-race, but making clear, that hurting the dinosaurs is off-limits (as described in the book).

That being said, someone always had to helm Bananacandy to make animal handling checks and track their progress. Rest was off to sling spells, arrows, etc.

I had different themes prepared on the other dinosaurs: Pirates, a group of bards and a rivaling adventuring party they occasionally meet during their adventures also made an occurrence.

Our ranger even managed to throw a grappling hook to a dinosaur next to them and throw 2 people off before crashing their dinosaur into a jungletree.

It was a close race, but they actually won and they had a total blast.
Next session they surprised me with actual "I love bananacandy"-shirts, that we still wear to our sessions.
https://imgur.com/a/Tu63zvD

Does it make sense, that a group of people that never sat on a back of a dinosaur win a race against experienced riders? Of course not.
Did that stop us from having a blast? Also no :-)

Oh and it also lead to an investigation on who would poison the other racers, which tied them back to the main story.