If you focus science explorations in your classroom on a yearly theme, consider water play/study. Carol M. Gross of Lehman College describes the many, many aspects to water play/study and connections to social learning, art, physical development, and social studies in her article “Science Concepts Young Children Learn Through Water Play” in the Dimensions of Early Childhood, vol 40 no. 2, 2012, the journal of the Southern Early Childhood Association.  (SECA is a regional organization that advocates for quality care and education for young children and professional development for early childhood educators.)
Dr. Gross draws from a large number of resources to fully describe the spectrum of activities with water. Her tables are so useful! She lists concepts, the explorations that can occur and describes meaningful conversation questions so we can really see the science in water play.
For example, while engaged at a water table or while cleaning tables, children can explore porosity, defined as permeability to fluids, exploring with sponges, cotton, cloths for everyday cleaning, or for exploration in a low container of water, and teachers can support the exploration by asking, What happened when you squeezed it? What did you find out about this material? Which material held the most water?
Water play/study is part of learning about topics such as, properties of materials, needs of living organisms, understanding motion, measurement, and making mixtures.
Thanks to Dr. Carol Gross and SECA  for supporting early childhood teachers in teaching science! Comment below to share how you use water play to teach science concepts in your program.
Peggy