https://proglib.io/p/best-math-test/
https://proglib.io/p/logical-mathematical-tasks/

2016
Abstract and Concrete (very good comments)
https://www.youtube.com/watch?v=7h2ZBIpVJ_Q

motivating sample
https://medium.com/google-design/google-photos-45b714dfbed1
    http://css-live.ru/articles/kak-my-delali-veb-interfejs-dlya-google-photos-zaglyadyvaem-pod-kapot.html

11 class
https://www.youtube.com/channel/UCtY5syy1yFzf-bwx-leu4FA
10 class
https://www.youtube.com/channel/UCrhrcNqmTVInY0WacHaAPtg
9 class
https://www.youtube.com/channel/UCUbrbCryCLjlfmruq5qJ2eA
8 class
https://www.youtube.com/channel/UCk2MAzMtaEl_9Jq95Q953fQ
7 class
https://www.youtube.com/channel/UCU5UBxAOqcXtviP3EsJrQ7A
6 class
https://www.youtube.com/channel/UC8hDfn4MyNpGrJFmBSVUkhA
5 class
https://www.youtube.com/channel/UCk7QZDMnjzHqvjoqvHpdZLQ
4 class
https://www.youtube.com/channel/UCWnBqF2Vgaa11sP2fcR4jVg
3 class
https://www.youtube.com/channel/UCpdPnf-FJUPoBmmHJW6hcMg
2 class
https://www.youtube.com/channel/UC-h19WUd1B8N98GG5ogQQ7A
1 class
https://www.youtube.com/channel/UC6DaMLuoBNAb0bqKgwJvRmA

volkov ege
https://www.youtube.com/channel/UCLDpIKDTFBSwIYtAG0Wpibg
bezbotvy
https://www.youtube.com/user/bezbotvy
infourok
https://www.youtube.com/user/upiterra/playlists
romanov - math and phisics
https://www.youtube.com/channel/UCnooVihOGi-BLP20XdW_vBw
math simple
https://www.youtube.com/channel/UCTx46B991tGoUfCey0Emp1A
EduLibNet
https://www.youtube.com/user/EduLibNet/playlists?view=50&shelf_id=7