The Duolingo website is intended for ages 13 and up, so it hasn't really been tailored for that age group. (Not that I don't want to see younger people on the website. Duolingo is an amazing resource, and I wish I had had access to it when I was younger!)

I don't use the app, so, I didn't realize there were social spaces on it. But, reading comments it appears they can access sentence discussions. If those sentence discussions are the same ones accessible to the website and you see inappropriate content, please contact a moderator (someone like me, with a green ring around their icon.) It's a little complicated, but if you can enter the website, go to the language forum that matches your course, you will see a tab called "Sentence discussions". From there, type the sentence into the search bar and you should find the discussion from the search results. Once you enter that discussion, snag the URL. Paste it to a moderator's Activity stream along with a short description of the situation and the username's of anyone involved in posting the inappropriate content. If that doesn't work or you don't have the time, you can contact abuse@duolingo.com The drawback is that it will take longer for the material to get removed going that route.

Meanwhle, if you are on the website and wanted to block someone from commenting on your Activity, you can do that. However, you can only block people one at a time. You'll find the instructions here http://i.imgur.com/nbuTLQv.png

I hope that helps!

You can use the app. There is no way to talk to other users.

No, you cannot, sorry.

I don't know why this is downvoted (not anymore, edit yet again). The mobile apps on iOS (in particular) and Android (discussions on sentences are available) offer this.

edit: if this is an option, mobile apps that is.

I agree that the phone/tablet apps are going to be the easiest way to go. If you don't have an Android or iOS device, then maybe you could look into emulators? http://www.macworld.co.uk/how-to/iosapps/how-run-ipad-iphone-apps-on-mac-or-windows-pc-3512222/

There's always the option of doing Duolingo together, or otherwise supervising them. I know it's not always practical to be there, and you shouldn't have to watch them like a hawk, but developing that sort of smart internet savvy-ness is something every kid needs to develop with a safe adult.

Does your parental controls software include the ability to whitelist and blacklist URLs? I think blocking "https://www.duolingo.com/translations", "https://www.duolingo.com/discussion", and "https://www.duolingo.com/comment" should block the social aspects.

I went back and edited my comment after some inspiration from my mentor. So, hopefully you'll find the improved version more useful. :).

I've used the app, and I didn't find a way to chat on the app so you can try getting the app. On the website, though, I don't think you can disable social interaction (you could block the site and just allow the app).

I am talking about the iOS app. It is recommended by my son's school. But, I just found out that they follow each other, email each other, etc... I do not think my son's school is aware of the interaction that is taking place ("how old are u?", "do you like kissing?", etc...)