This is a great activity because it builds the muscle control needed to learn to write by holding a paint brush, they get practice recognizing letters, plus it is better for toddlers and preschoolers to write, draw, or paint standing up because they will have more muscle control.
Also on these boards
Here's a fun summer craft for kids that also provides fine motor and counting practice~ A Paper Plate Octopus!
Feather Color Sorting and Fine Motor Activity from Fantastic Fun and Learning
A push pin Geoboard with rubberbands. Made completely by child!
Making Words with Magnetic Letters