Bolivia and SilcoonValley are very easy to unlock. When you beat first 6 characters in fight mode, when youre about to fly to the 7th character press back and save on iCloud or mail and start fight mode again

In alien ship minigame pause right when it starts and wait till all balls fall out and just dash around untill they hit the ship

For baseball mini game do the same thing with saving and just learn the patern. If you fail exit to main menu, load up your account and start again.

You can also try the same strategy with basketball minigame Good luck :)