What is a good workout for a 12 year old girl to do daily?

Like not too grueling or harsh or anything, just simple and it can be all kinds of things. Please don't say that 12 year old girls don't need to workout and shouldn't worry about their weight because that's not true. Again, it needs to be realistic and not something that would give a 12 year old girl big arm muscles, just something to keep fit, Thank you in advance! :)