Grammar and Composition

Wheeler's Graded Studies in English
Wheeler's Graded Studies in English: First Lessons in Grammar and Composition

Harvey's Grammar Series
Harvey's Elementary Grammar and Composition (4-6)
Harvey's Practical Grammar (7-8)
Key to Harvey's Practical Grammar

Maxwell's English Series
Primary Lessons in Language and Composition (1-4)
First Book in English (3-5)
Introductory Lessons in English Grammar (5-8)
Maxwell's School Composition (5-8)
Advanced Lessons in English Grammar (Middle-High School)
Writing in English (Middle-High School)

Progressive Composition Series
Progressive Composition Lessons Book 1 (3-4)
Progressive Composition Lessons Book 2 (5-6)
Progressive Composition Lessons Book 3 (7-8)

Fleming's English Series
A Child's Composition Book (4-6)
A Composition-Grammar (7-8)
Practical English for High Schools (High School)

Dalgleish's English Series
Outlines of English Grammar and Analysis for Elementary Schools (Elementary)
The Progressive English Grammar
Grammatical Analysis
Introductory Text-Book of English Composition (High School)

Grammar
KISS Grammar (2-11)
Weld's Progressive English Grammar (All Grades)
McGraw-Hill Treasures Workbooks (K-6)  **Added 7/20/13

Composition
Elementary English Composition for High Schools and Academies (High School)
Purdue OWL English (7-12)

Grammar and Composition
Scott Foresman Online Grammar and Writing Handbooks (1-6)  **Added 7/19/13

Complete Curriculum Options

Preschool
Brightly Beaming Resources (PreK-Early Elementary)
First School Preschool (thematic units, Pre-K-K)
Read to Me and ABC (PreK) **Added 7/24/13

Charlotte Mason
Ambleside Online (K-12)
Mater Amabilis (Catholic, K-8)
Higher Up and Further In (AO-inspired, K-12)
Tanglewood School (1-8)
Simply Charlotte Mason Curriculum Guide (K-12)
Milestones Academy (K-10)

Classical
The Classical Curriculum (PreK-12)
Classical Homeschooling (K-12)

Primarily Public Domain Text-based
An Old-Fashioned Education (K-12)
Your Free Homeschool Library (K-12) - While I do not provide a schedule or specific book recommendations, I have gathered a plethora of vintage textbooks and categorized them by grade and subject, making it simple for a teaching parent to choose what they need to teach most of the core subjects.

Primarily Web-Based
Lesson Pathways (K-5)
Easy Peasy All-in-One Homeschool (K-High School)
EZSchool (K-12)
DiscoveryK12 (K-12) *Added 9/6/16*
HippoCampus (covers math, science, social studies, and religion, Middle-High School)
Connexions (High School-Adult)

Flashcard/Worksheet-Based
Free World U (K-12)
Head of the Class (K-5) *Update 7/5/13* This site appears to be closed, but I will leave here in case it returns.

Core Knoweldge-Based
Baltimore Curriculum Project Core Knowledge Lessons (K-5)

Single Year Unit Study
Teaching with God's Heart for the World (Elementary)

School Curriculum Guide
Hillsdale Academy Curriculum  (requires free registration, K-12)
Liberty Academy Online Curriculum Guides (scope and sequence, 3-12)

Reformed
Puritan's Home School Curriculum (K-12)

Memory Work

Chants, Jingles, and Songs
Association of Classical & Christian Schools List

Memory Work Resources
Circle Time and Memory Work