A three-year-old can ride Slinky Dog Dash at Disney's Hollywood Studios as long as they meet the height requirement of 38 inches (97 cm). Because many three-year-olds are right at or slightly above this height, it is a very common "first coaster" for that age group. However, just because they can ride doesn't mean every three-year-old should. Slinky Dog Dash is a "family coaster," but it is more intense than the Barnstormer at Magic Kingdom; it features two launches, a few significant drops, and "airtime" hills that can be a bit startling for a toddler. If your child is brave and enjoys smaller drops, they will likely love it. If they are sensitive to noise or speed, it might be better to start with the Toy Story Mania or Alien Swirling Saucers in the same land. It is also important to note that if your child is exactly 38 inches, Disney cast members will measure them twice—once at the entrance and once right before boarding—to ensure their safety. If they don't meet the height, or if they get "scared" at the last minute, you can utilize Disney's Rider Switch service so the rest of your party can still enjoy the ride without having to wait in the full line twice.