‎States of Matter


Play with different solids, liquids, and gases. Discover how changes in temperature affect states of matter as you freeze soda, pop popcorn, melt gold, and more! Answer the burning question, “Does it melt?!”

States of Matter is No. 11 in Tinybop’s award-winning Explorer’s Library, a series of apps designed to introduce kids to big ideas. Other Explorer’s Library apps include The Human Body, Plants, Simple Machines, The Earth, Weather, Homes, Skyscrapers, Space, Mammals, and Coral Reef.

Each Explorer’s Library app teaches kids foundational science. Kids learn by playing, experimenting, observing, asking questions, making guesses, and finding answers. We hope each app inspires conversations between you and your kids and sparks more learning in the world around us.


  • Freeze soda, pop popcorn, melt gold, and more
  • Explore the shape, color, behavior, sounds, and movement of different states of matter.
  • Discover how different objects behave in extreme temperatures (from -500 °F to 5500 °F!). Watch solids melt, liquids freeze, and gases liquefy as you change the temperature.
  • Explore phase changes and discover which changes cannot be reversed.
  • Explore how molecules move at different temperatures.
  • Discover the melting and freezing points of different objects.
  • Interactive text labels in 30+ languages teach vocabulary.
  • Aligns with Next Generation Science Standards (NGSS).
  • Open-ended activities with no rules. Curiosity and creativity are rewarded.
  • Original artwork by Jeanelle Mak Petrillo.
  • Original sound design.