For a twist on traditional easel painting (which secretely drives me crazy with the big brushes and the mess it makes!) I put out small paint squirt bottles (in the cake making supply isle at Michaels). Filled with red, white, and purple the children put small amounts in the supplied paint pallet and tint it with the white creating lavender and pink! They can use the dark colors too as there's enough compartments in the pallet for lavender, pink, white, dark red, and dark purple.
With smaller brushes supplied they are able to paint more detailed pictures. Not pictured is a paint holder with water in it to rinse their brushes before changing color and a damp sponge to dab their brush clean and dry.