What you're trying to do is actually quite simple, but you will have to do it individually for each app. First, make sure you have the latest release of iOS 8 (this is not completely necessary, but recommended). Next, go to the Settings app and scroll down until you find the application you want to disable notifications for on the lock screen.
Now, click that cell and scroll down on the presented screen for "Notifications"
Now, on this screen there is a slide that says "Show in Lock Screen". Disable this (like this):
Now you're finished! Let me know if this does not work for any reason.