Hi Sheri! I have the bravery level of a small child, so I feel qualified to answer your question! Even though the Barnstormer is considered a kiddie coaster, it's a thrill ride in my book! I'm a ride wimp, but even I
can handle
Big Thunder Mountain, which is longer, but in my opinion, no more intense than the Barnstormer. If your granddaughter is 40 inches tall, she can ride this
train coaster that, similar to the Barnstormer, has small dips and twists but no
big drops.
Test Track at Epcot is another great beginner thrill ride. The height
requirement is also 40" and although the car goes really fast, there aren't any
drops.
I hope you have a wonderful time with your granddaughter! Come visit us again at the Moms Panel if you have more questions!