(Goblin is 30 months)
I rarely plan an art activity with Goblin, but we do a lot of art. Most of the art that happens in our house is accidental.
I think art is an important activity.
For babies and toddlers art is a form of sensory play, its is primarily about the process: experiencing the gloopy paint between your fingers and toes, seeing the result of moving a pen across paper, feeling the feathers and pompoms as you stick them to the card.
Occasionally your child will create something that isn't a torn soggy mess of paint and glue. When this happens with Goblin I always try and display it - because creating is a form of expression and I want Goblin to see from an early age that I value his expressions and am proud of his creations.
And art is about independence. The more freedom a child has to create independently, the more confidence they'll have to do it, and that will spill over into other activities.
How do you make art child led?
1. Make sure art supplies are within reach.
2. Teach from the beginning how to use the supplies responsibly to minimise mess and stress.
3. Try to say 'yes' to art activities even when it means mess and stress.
Accessible art supplies may make you feel anxious -"oh goodness, paint up the walls and on the sofa". But you can introduce them in phases.
Goblin has had
Crayola washable felt tip pens
in a box on his desk ever since he was tiny. These pens wash off walls, sofa material, clothes and skin. So even if your child does go nuts it won't be a permanent disaster. From the minute we introduced them we taught two rules, always put the lids back on, and only draw on paper. Now learning is a process so I am not claiming that Goblin has never left the tops off or drawn on stuff thats not paper - in fact he loves drawing on himself. But we have set the boundaries and normally he respects them.
For the last six months Goblin has also had full access to a huge box of wax crayons. You may wonder why the pens came before the crayons, the answer is simple - crayon is way more difficult to get off floors, walls and furniture. So we needed to ensure he understood the 'draw on paper' rule first.
And at Christmas he was given some
Melissa and Doug Stamps 
(with washable ink). These live on the shelves where he can reach them when ever he wants.
As well as the pens, crayons and stamps we have lots of
Ready Mix Paint . When Goblin was younger we kept them on a shelf out of reach but recently we have moved them to a basket where he can get to them when ever he wants.
Getting from 'inaccessible paint' to 'accessible paint' was a staged process. First we taught Goblin that all painting must be done on a mat. The mat has always been accessible and we have encouraged him to put the mat out himself. So now he knows to put the mat down before painting.
Second, while the paints where still out of reach we showed him how to put the tops back on and how to clean any spills.
Finally, I know that if Goblin asks to paint it is going to get messy. Goblin likes to paint with his whole body - Feet, hands, face! We've had to teach him not to move off the mat when he's covered in paint. Instead we taught him to "shout for help". Sometimes help is just a simple wiping the hands, but more often than not its an entire hose down in the shower.

Saying Yes to mess and stress
Getting messy is fun for most toddlers. I tend to let Goblin do art whenever the mood takes him. He has a really annoying tendency to want to do art when he has just got clean. The photo at the top of this post was taken ten minutes after his bath. But why say no? What am I trying to keep him clean for? "A toddlers work is play" and sometimes that involves getting messy.
We don't have any clothes that I won't let Goblin paint or draw in. All the mediums we use wash out so if he gets paint - sorry that should be When he gets paint on himself, I can just pop the clothes in the wash. His bursts of painting are often short lived, so even if we are going out in half an hour, I'll usually still consent to an art flurry on the basis that he'll usually be done and cleaned before we go out.

If Goblin goes out covered in paint, I just hope people will see what I see - a child who has had a fun day's play
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