In a medium bowl, whisk together the eggs, half and half, sugar, and ground cinnamon until smooth and fully combined, with no streaks of egg remaining.
Crush the Fruity Pebbles into small, pea-sized crumbs (a zip-top bag and rolling pin works great), then spread them in a large shallow bowl.
Working one slice at a time, dip the bread into the egg mixture and let it soak for about 30 seconds per side, until saturated but still holding its shape.
Transfer the soaked bread to the crushed Fruity Pebbles and press the cereal firmly onto both sides with your hands so the coating sticks.
Spray the air fryer basket with cooking spray. Place the coated slices in the basket in a single layer, making sure they don't touch or overlap; cook in batches if needed.
Air fry at 320 degrees F for 3 minutes, then carefully flip each slice and air fry for another 3-5 minutes, until the coating is golden and crisp and the center is set.
Serve immediately with maple syrup, whipped cream, or fresh berries.