If you are asking about the last gem in the Jungle Ruins quest, you have to play Bear 2 Bear Baseball and you or your opponent must get a home run to get the gem. I hope I helped and good luck!
You have to play Bobbing Fur Apples to get the 3rd gem on the Jungle Ruins quest. It's on level 1 and is in a corner out of the bucket.
To find the 4th gem, you have to go to the farm and play the game, Bobbing Fur Apples. While playing the game, look at the top left and you will find the red gem. Click on the gem and return to Jungle Ruins.
The fifth gem will be available if you go to base ball at sportsplex and aim the ball slightly to the left and hit the mouse at the moment when the arrow points at the advised place and you make a home run then the gem will be in your midst.
The fountain in the town square
Go to the game bobbing for apples then click on the red gem on the side of the bucket and you have your gem!
The first gem is in the game dive beary deep
You have to play Bear-2-Bear racing and win to get the second gem.
at the top of the tree in the heart of the forest.
It is in the sporplex and you have to play the baseball thing
You have to get a home run on the baseball game
for the jungle ruins quest the last gem is in bear-2-bear baseball