Slippery Slopes includes challenges that award you Stars and Gifts.
Basically you need to get to the finish line before your shell temperature reaches 100 degrees. While you are on the ground, your temperature will rise. To score points, you need to be in the air. For each second you are in the air, your multiplier will increase, but is reset once you touch the ground again.
Stars are attributes that can be applied to either your Dive speed or Score bonus. Certain levels can be completed easier with a higher Dive Speed and certain levels can be completed easier with a higher Score bonus.
Gifts offer bennefits as well.
Slipper Slopes Free includes:
1 set of Binoculars to increase your view distance.
1 can of Grease to increase your Dive Speed.
1 Helmet to increase your Score bonus.
The not free version offers different variations of the above.
Also, there is an update in the works for the not free version that will allow the player to generate their own levels.
I hope this helps. And if you do decide to download and try it, please let me know if you have any suggestions or problems. You can find Slippery Slopes on Facebook, so feel free to send messages there as well.