The main content of Beijing’s Spring Festival class notes is as follows:

It mainly introduces that Beijing’s Spring Festival starts in the early days of the twelfth lunar month and does not end until the 19th day of the first lunar month. People cook Laba porridge and soak Laba garlic on Laba day. The 23rd day of the twelfth lunar month celebrates the New Year. New Year's Eve is very lively, but the scene on the first day of the lunar month is completely different. The Lantern Festival is another climax of the Spring Festival. Until the 19th day of the first lunar month, the Spring Festival ends.

The main idea of ??the paragraph:

The first part (sections 1-7): Describes the situation of Beijing citizens preparing to celebrate the Spring Festival in the twelfth lunar month.

The second part (sections 8-11): Describes the grand celebrations of Beijing citizens on New Year’s Eve, New Year’s Day and the beginning of the year.

The third part (verses 12-16): Describes how Beijing citizens celebrate the Lantern Festival.

The fourth part (section 17): Describes the differences between the old and new societies in celebrating the Spring Festival.