There are lots of great class clips for different art and design skills on the bbc.
10 minute photo challenge – Take as many interesting pictures as you can within the house. Make a collage from them on the computer.
Pebble painting – find pebbles in the garden to paint (you could use paint leftover from DIY jobs)
Draw using different materials (eg. chalk on outdoor stone)
Pictionary – draw something in 60 seconds. Other people must guess what you have drawn.
3 marker challenge – choose 3 different pens/pencils/chalks/crayons with a blind fold on. Draw the best thing you can think of with these colours.
Tie dye t-shirts using old or charity clothes
Create collages using wallpaper leftovers, magazine cuttings, anything you can find and see what creations you can come up with. Can you create a bigger picture using lots of smaller pictures?