i can't vouch for entirely youth friendly content, but most of what i have browsed on Vimeo.com seems to be great quality and style. The searches for time-lapse videos and nature stuff turn up amazing!
a couple of my faves (also seem to be staff picks):
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|a-sorta-fairytale , Alexa2015 , anisaer , annanyc , bananabee , BirthFree , Daffodil , Deborah , Dovenoir , Erica Sandwall , floss&ferd , gizzypeach , heyxxmcfly , Hopeful2017 , joycef , katelove , LiLStar , LoveDiva , Lucee , MDoc , Michele123 , Mirzam , mjkirch , moominmamma , NaturallyKait , notnever , perspective , RollerCoasterMama , samaxtics , shantimama , Skippy918 , sollicitus , Springshowers , zebra15|
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