https://www.bbc.co.uk/bitesize/subjects/zmx6fg8

This is aimed at second level and covers all the basics.

https://www.britishcouncil.org/sites/default/files/the_great_mandarin_chinese_language_challenge.pdf

Try this Mandarin Challenge

https://scilt.org.uk/TheHappyEmperorandotherstories/tabid/4605/Default.aspx

E-books to learn Mandarin

http://www.bbc.co.uk/languages/chinese/

Lots of different videos here for beginners

https://www.pandatree.com/FreeLearningMandarinResources

Lots of resources for students and teachers

https://www.bbc.co.uk/bitesize/subjects/zsbc87h

KS2 Mandarin

https://coffeebreakacademy.com/p/coffee-break-chinese-season-1

Podcasts in Mandarin

https://www.education.vic.gov.au/LanguagesOnline/chinese/chinese.htm

Lots of drill here with the basics