Drempel 1
https://schooltv.nl/video/de-oerknal-het-begin-van-alles/
https://schooltv.nl/video/de-oerknal-hoe-is-het-heelal-ontstaan/#q=de%20oerknal
https://www.youtube.com/watch?v=1nWZV2fKo-I
Drempel 2
https://www.youtube.com/watch?v=I68LYiVd8zU
https://www.youtube.com/watch?v=rGSQS_idhq0
https://www.youtube.com/watch?v=D4bDw1YlyDQ
Drempel 3
https://www.youtube.com/watch?v=Cxuzz7tHfIc
Drempel 4
https://www.youtube.com/watch?v=4lSQE8LCDiU
https://schooltv.nl/video/het-klokhuis-planeet-aarde-het-begin/
https://www.ntr.nl/html/micrio/schooltv/aardlagen/
Drempel 5
https://www.youtube.com/watch?v=8lX-VwWSRzk
https://www.youtube.com/watch?v=lnh5NFX4OAU
https://www.youtube.com/watch?v=NPZ2y5tI68Q
Drempel 7
https://www.youtube.com/watch?v=8LvgagMupjs
https://www.youtube.com/watch?v=XyPKb2ZDcC0
Drempel 8
https://www.youtube.com/watch?v=8ysziqFOOXc
https://schooltv.nl/video/histoclips-afl-8-de-industriele-revolutie/