Cooking
It's important that children understand how and where the food on their plates at mealtimes comes from. Use a cooking activity to explain this, as well as provide your family with something to eat. Select something that children enjoy eating so they become excited about eating it and allow them to get involved, such as mixing ingredients in a bowl rather than chopping vegetables with a sharp knife. As you work your way through the ingredients explain information, such as that an egg comes from a chicken.
Fort Building
Although an activity usually associated with outdoors, fort-building is just as fun in the family home. You'll need to find somewhere suitable to build the fort, where there aren't any safety hazards like glass that might fall. With tape or weighted down items, hang bed sheets around the area to conceal a closed off area of the room where children play in. Make sure you create a small entrance where the children can crawl in and out of.
Board Games
For studious children you could propose a traditional board game such as cards or chess. They're an excellent way for children to keep their brains working while they're not at school and adults can also enjoy themselves. Some games like jigsaw puzzles can last hours.
Artwork
There are hundreds of different types of artwork that children can enjoy at home. Base your project around the time of the year; at Easter they could decorate an egg with paint and at Christmas they could draw a Christmas tree.
Languages
You could decide to learn a language with children. Being able to speak multiple languages is becoming more and more important for certain jobs and in certain industries. You can do this by listening to songs, trying to read a book or watching a film. It's far easier for children to learn languages than adults, so you'll have to work hard to keep up with them.
Paper Airplanes
Making paper airplanes is great fun and teaches children to think about geometry. You can download a number of designs and styles from the Internet, all of which are made with a single sheet of paper.