Here are some resources for young learners.
Books and audio books
Short stories for kids on the British Council website
Magazines and websites
Dobble - this is one that I need to play in German so that I can practice adjective endings. Don't just say 'Dobble' but say 'blue hat' or 'yellow magic wand'.
Pictionary - kids love playing it. Drawing pictures can be a good strategy for learning new vocabulary.
Articulate for kids - might be a bit tricky for young kids but you can make up your own version. All of my students who have played this game love it.
Stadt, Land, Fluss - play this in English or German or any language you like. Make up your own categories such as adjectives to describe people if you also want to practice word classes with your child (nouns, adjectives and so on)
Shut the box - this is a great game for mental arithmetic as it is so addictive.
I'll add to this post as I find more resources.