What grade of textbooks does Cang Xie use to create characters?

Cangjie's word-making is from the fifth-grade textbook.

Cang Jie Zao Zi further explores the mystery of Chinese characters from the aspects of their origin, evolution and structure, and emphasizes the standardization of their use. Cang Xie played an important role in the production of Chinese characters and made endless contributions to the prosperity of the Chinese nation. Without Cangjie's word-making, there would be no great works spread around the world, and without Qin Shihuang's "book with the same text", there would be no long history of Chinese civilization.

The story of Cangjie's word-making:

Cang Xie is the official historian of the Yellow Emperor. In the past, people used to tie knots to keep records, that is, make a big knot for major events, make a summary for minor events, and make a link for connected things. Later, it was developed to carve symbols on wood and bamboo with a knife as notes. With the development of history, civilization is gradual, things are complicated and there are many famous things. The knotting and carving methods of wood can no longer meet the needs of life, and there is an urgent need to create words.

After the Yellow Emperor unified China, he ordered his historian Cang Xie to find a way to create Chinese characters. Therefore, Cang Xie "initiated a contract conclusion instead". Cang Xie built a house on a high platform on the south bank of Wei River and devoted himself to writing. However, he thought hard for a long time and didn't say anything.

One day, while Cang Xie was thinking, he saw a phoenix flying in the sky, and what was in his mouth fell right in front of Cang Xie. Cang Xie picked it up and saw a hoofprint on it, but Cang Xie couldn't recognize it, so he asked a hunter who happened to come. The hunter looked at it and said, this is the hoofprint of a brave dog, which is different from that of other animals.

Cang Xie was encouraged by the hunter's words. He believes that everything has its own characteristics. If we can grasp the characteristics of things and draw images, everyone can know them. Isn't this a sentence? Since then, Cang Xie has carefully observed the characteristics of various things, such as the sun, the moon, stars, clouds, mountains, rivers, lakes and seas, as well as various animals and birds, and drew graphs according to their characteristics.

On the day of the Grain Rain solar term, I had an epiphany and created many hieroglyphs.