Answer:
Well, the biggest reason most cases get to the supreme court is if the largest court of a state appeals it to the court deeming the matter to be a constitutional issue. Our example will be about Bobbert. Bobbert has been caught with a firearm and he has just been released from prison charged with second degree murder. Now, Bobbert may have been caught with this firearm, but in his defense, it was a family airloom dating back to the 1800's. This would be a constitutional case, as his right to bare arms is being infringed upon here. The highest court of Bobberts home state, Norweiga, decides this is a constitutional problem and appeals it to the state court. Now, before the court decides to consider taking the case, four of the justices must agree to grant the petition. If the case decides to take the case, then congratulations! Bobbert may get his fire arm back!
Hope this helps!
(please note, I have almost no experience with law....and Norweiga is not a state in America)