Could have a station where kids make their own daffodils. The Imagination Tree: Daffodils for St David's Day. Card - 6 petals, stick with sticky fixers, paint egg box compartment and stick with sticky fixers - done and no mess!
A complete resource of spring activities for children :: spring carfts, art, math, literacy, science and play
123 Homeschool 4 Me: April Creative Writing Prompts for Kids
Making an inference, creating a diagram, seed experiments. So many great ideas in this post for a plant/seed thematic unit!