That is the best way though, that's how children learn. They don't learn by reciting verbs parrot fashion and knowing what a suffix is.
My son has just installed Babbel for iPad and is really enjoying it.
It's similar to Rosetta, and you can keep going over things until you grasp it.
Some of it is free, then there's an option to pay for 6 months, I think he said its around £30, so is much cheaper then Rosetta.