适合年龄
9岁左右
绘本简介
The Black Stones tells the story of twins who learn to put aside their differences and get along with each other. Tala finds two obsidian stones and wants to learn more about how they were formed from a scientific viewpoint. Her brother, Paco, isn't interested in science and wants to find out if the stones are lucky charms or have magical properties. Their mother forces them to work together to find the answers. The twins discover that they actually enjoy working together.
《黑石》讲述了双胞胎学会抛开分歧，和睦相处的故事。 Tala 发现了两颗黑曜石，想从科学的角度详细了解它们的形成方式。 她的兄弟 Paco 对科学不感兴趣，想知道这些石头是幸运符还是具有魔法特性。 他们的母亲强迫他们一起努力寻找答案。 这对双胞胎发现他们真的很喜欢一起工作。
RAZ有严密的分级体系：根据全文词汇数、高频词词汇数与比例、低频词词汇数与比例、句子长度、句子复杂度、句式、插图信息量、思想深度、主题等多个角度，将整个阅读体系分为aa，A-Z共27个级别。
RAZ旨在帮助孩子找到适合孩子水平的级别，通过在同一级别下的大量阅读逐步提高孩子的阅读能力。
RAZ按难度分为27个级别，AA—C这4个级别对应幼儿园阶段; D—J这7个级别对应美国小学一年级;K—P这6个级别对应美国小学二年级;Q—T这4个级别对应美国小学三年级;U—W这3个级别对应美国小学四年级;X—Z对应美国小学五六年级(相当于国内高中毕业)。
