I love your post with the detailed explanation on the importance of sensory play and child-leading play.
In my home childcare I use sensory material everyday and include free-play in our daily schedule as to provide opportunity for social interactions between the 3 toddlers in my care without me guiding it. It is, in my opinion, the best way to asses their current development in language, social-emotional skills, cognitive and depending on the activity they are engaged on, their gross and fine motor physical abilities.
The most common sensory materials we use are wooden cookies and logs, pipe cleaners and play-dough, water and sponges, leaves, pine cones and rocks, and different fabrics, etc.
For Easter they decorated eggs using paint and later, after they dried they used stickers. It is amazing the fascination of toddlers with stickers.
Thank you for sharing and happy Easter!