Sagebooks is an excellent curriculum that uses spaced repetition and short stories to teach kids how to read 500 Chinese characters and basic sentences. Simplified and traditional Chinese versions are available.
Leveled reading is a strategy that encourages kids to read books that match their reading skills. Here is a detailed comparison of Chinese leveled readers that we have used.
We love the 樂樂文化 Le Le Chinese Reading Pen system, which teaches 1000+ traditional or simplified characters through 300 stories! My kids love the stories, and the reading pen is so helpful for non-fluent families.
My daughter enjoyed the 红蜻蜓学前阅读计划 Odonata Chinese Leveled Reading Series, a story-based curriculum that teaches 1200 Simplified Chinese characters. The series comes with workbooks, flashcards, and CDs which can be purchased separately.
四五快读 is an excellent, low-cost curriculum that teaches 825 simplified Chinese characters through stories and exercises. My daughter was ready for Chinese bridge books after this series!
The Greenfield 我自己会读 I Can Read series has 96 short, humorous children's stories that are illustrated beautifully and build reading confidence. The CDs give exposure to native Mandarin or Cantonese. In addition, workbooks and flashcards are included.