See the complete review in 102 Top Picks for Homeschool Curriculum.
A Beka's language books for grades K through two are integrated with their resources for teaching phonics, reading, spelling, and handwriting, along with some grammar and composition. This review, as well as my selection of the series as a Top Pick, refers to the rest of the series for grades three through twelve.
A Beka is a very traditional program with worktexts (except for grades 11 and 12), lots of practice exercises, drill, review, and diagramming. The series also has especially notable Christian (Protestant) and patriotitc content throughout the exercises.
Lesson instructional information is in the student books, so students can work independently through the most of the lessons. Teacher editions have reproduced student pages with answers overprinted. There are separate student test books and test answer keys. Homeschool editions of curriculum guides help you coordinate lessons in these books with other A Beka books for spelling, handwriting, and reading. They also expand upon some of the composition assignments. If you plan to rely on A Beka for composition instruction, you might want the curriculum guide, but otherwise they are not essential.
Books and their suggested grade levels are:
Language 3 - grade 3
God's Gift of Language A - grade 4
God's Gift of Language B - grade 5
God's Gift of Language C - grade 6
Grammar and Composition I - grade 7
Grammar and Composition II - grade 8
Grammar and Composition III - grade 9
Grammar and Composition IV - grade 10
Handbook of Grammar and Composition (plus Workbook V) - grade 11
Handbook of Grammar and Composition (plus Workbook VI) - grade 12
While the books for K through grade six are printed in full color, the upper level books are not. Students in 11th and 12th grades use the ungraded Handbook of Grammar and Composition in conjunction with a workbook for each level.
Especially in the upper grade levels, you need not (and in my opinion, should not) use these books every year since they repeat and review much of the same content year after year, gradually adding more topics.
They are much stronger on grammar than composition, so you might want to use them for that purpose and other resources for composition. They really do a thorough job on grammar, including punctuation, capitalization, and other related skills.