I teach the English portion of 3rd grade at a Portuguese dual-immersion school. Duolingo has done WONDERS for my Portuguese, because it's such an incredible learning tool! Is there a kid-friendly version for educators to use? In some of my earliest lessons I learned beer=cerveja and vinho=wine, which an 8-year-old really doesn't need to be exposed to...particularly when Red Ribbon Week rolls around! ;)
If you create a teacher account "Duolingo schools" you can deactivate mature words.
Have you tried "Mondly Kids" (Android app)?
I have not seen / used it personally but it was announced to me when I clicked in the settings on the web of my Mondly tree (I am Premium).
I am using it to learn / practice Portuguese (BR).
It is just my opinion: parents tend to be overly protective... I cook beef with wine and chicken with beer, and I tell the truth to my children. Is there anyone who think that a 8 year child don't know what the beer is?
I am sorry I can't put here a list of questions my children of <9 age ask me when they returns home, because this page would become red :)
I can take into account religious or cultural arguments, that's another discussion, but at this age these are terms good to be kept in mind, at least in the idea of avoiding risks.