Thank you for your interest in Roller Coaster Rampage. There is a freeride mode where you can simply create coasters on the fly, with no campaign involved.

As IGN described it in their review
"Instead of constructing tracks using a more technical editor-style interface, you direct your coaster around the park in real-time and the track builds itself out behind you. It's an inventive approach to coaster crafting that allows for some real artistry and intuition in the tracks you make."

Also, here is a post from another customer. This was posted to the old forums last year.

"For those of us with kids, I cannot recommend Rollercoaster Rampage enough.

Absolutely ZERO deaths
Fun
Accessably creative and cool for kids to swap seats to ride each other's rollercoasters
Colourful
Decent 3D
Destructive environments (but not gratuitous)!
and cheap at £7 too.

Thinking about kids, Newtonian physic seem to be at play in RCR. What I would love to see is the option to choose when to quit the freerun. That way my kids could stop the track and have fun 'discovering' physics (if you know what I mean) when they ride their 'coaster! They'd love that.

On that note, is it possible to let the train slide backwards on a track if it hasn't enough momentum to carry over a peak? If so, it would provide opportunities to discover simple harmonic motion (I think) in play. Obviously, they wouldn't know what they were watching was SHM but they would be able to experience it. I think I would find this a useful teaching resource in a classroom!

Regardless of whether or not the abovementioned ideas are possible, thanks from one very happy Dad!"