I put out a mixture of normal paint and some glitter paint, as they started to paint they talked about how they could still see their reflection and then they would paint over their reflection, giggling saying "now I can't" and repeating this till the whole mirror was covered in paint.
They then discovered by dragging the paint brush through the paint and /or twisting it around they could produce different patterns.
Washing up produced more interest as they realised the water made different patterns as the paint was washed away and that they could see their reflection again.
It was then back to the table to start painting again, they repeated this several times.
They attempted hand prints on the mirror
which left behind an interesting pattern.
They also enjoyed writing and drawing patterns on the mirrors.