Well I dont think children should do ALL the housework, but certainly they should help out with chores-age appropriate of course. What a 5 yr old can do, isnt the same of what a say 15 yr old can do.
My children aged 6, 4 and 22 mos ALL help out in the house! The oldest too, need to put their dirty clothes in the hampers according to dark and lights-They need to pick up their toys and tidy up after they're done.
Also they help out setting the table, and bringing their plate back into the kitchen. My 22 mos old daughter helps setting the table as well at times! She thinks it's a game but does a wonderful job!
So yea children should HELP out with chores, it's not their job either to be the cleaning crew but they can certainly contribute to the running of the house. Depending on their age, let's say teens should be doing their own laundry and cleaning of their own room, they should also be helping out with dinner preparation and cleaning up, etc