Here is a free online game to learn mainly vocabulary. You will have to create an account and are free to use it.

In this lesson you have to listen to the word and find it on the picture

It has multiple topics to choose from:

And it has multiple types of exercises on each topic.

One tip: don't forget to pick Luxembourgish language on top right corner:

Small note: under Linux-based systems it works best with Chrome/Chromium browser, in Firefox it has some glitches.