This is the main "text" for Horizon's spelling and vocabulary program for first grade. The Student Book is full-color and contains the word list, worksheet pages (for the suggested activities), and practice pages.

Level 1 (generally 1st grade) covers: short vowel words, long vowel words, contractions, plurals, suffixes (e.g. –er), consonant digraphs (e.g. kn), vowel digraphs (e.g. au), compound words, consonant blends, synonyms, antonyms, homophones, and r-controlled words.

The program consists of 160 lessons for a 32-week academic year. A teacher's guide, student workbook, and student dictionary are sold separately.