I have been teaching Japanese for last 15 or so years and two best textbooks I have come across are:
What makes the two stand out is that they are perfect both for self-studies as well as learning with a teacher/tutor. Unlike many textbooks in the market that offer few or no exercises, these offer plenty practice for the words, kanji and grammar that you learn. That is the best way to make sure that you don’t forget what you learn the next day, as it seems to happen way too often.
