I'm in level 2 as of now (third semester learning it so far), and have been learning from a book called "Genki"
http://genki.japantimes.co.jp/index.en.html
They're a little strange in terms of how they prioritize vocabulary (we learned hospital before we learned house), but they teach structure really well.
いま、ぼくはさんがっきのにほんごのじゅぎょうです。 ”げんき”のきょうかっしょうをつかっています。
oh, and this is how i learned the basics (the first 6 chapters, so the first semester's worth of knowledge)
Lesson 1:
Question sentences
Noun1 no Noun2
Lesson 2:
kore/sore/are/dore/kono/sono/ano/dono/koko/soko/asoko/doko
mo
jya nai
Lesson 3:
Basic conjugation (masu)
Frequency adverbs
the particle wa
masen ka as a suggestion
Lesson 4:
arimasu/imasu
Past tense
takusan
time of day (ichiji, niji, etc.)
to (as and)
Lesson 5:
Intro. to i and na adjectives
mashou
basic counting
Lesson 6:
te form
te kudasai
te mo ii desu/te wa ikemasen
kara
Monster Hunter: pissing me off since 2010.