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Real Science Teaching. Real Classroom Experience.

I’m Amy Brown, a veteran high school biology and chemistry teacher, wife, and mom who understands the daily reality of lesson planning, grading, meetings, and everything in between. I know what it feels like to have too much to do and not enough time to do it.

After decades in the classroom, I’ve created rigorous, classroom-tested biology and chemistry resources that save you planning time while still delivering strong, meaningful science instruction. Every lab, activity, and lesson is designed to move students beyond memorization and into real scientific thinking.

If you want your students excited about science and thinking deeply without spending your entire weekend planning, you’re in the right place.

Amy Brown Biology and Chemistry Teacher

“I just love getting kids hooked on science.”

The Perfect Hands-On Experiment for Visualizing Osmosis and Diffusion


I love it when I get to this point in my biology curriculum. We have covered the skills of scientific measurement, scientific method, and microscopy. Now the students are prepared to use these skills on more complex topics, and the labs get much more interesting. The concepts of cellular transport, structure of a membrane, movement across the membrane, active and passive transport, cytolysis and plasmolysis are leading us to more complex topics. A solid knowledge of these concepts is needed before diving into cell communication, photosynthesis (thylakoid membrane transport) and cellular respiration (cristae membrane transport).  As students develop their knowledge base, it becomes like a "connect the dot" puzzle. The student has all the dots, and you (as the teacher) are leading them from dot to dot, helping them to make those important connections.

Labs involving cellular transport are often very simple, but they pack an educational punch. The first transport lab I do is a very simple lab called Osmosis and Diffusion: Transport Across a NonLiving Membrane.

Pieces of dialysis tubing are filled with either a glucose or a starch solution which is then placed in a beaker of water. In the beaker containing the starch bag, iodine is added to the water in the beaker. In the beaker containing the glucose bag, students used a glucose test strip to determine if glucose is moving across the membrane. 



Results are recorded after 20 minutes, and again after 24 hours. The results are dramatic and my students immediately grasp the concepts taught by this lab:  
  • The smaller the molecule, the faster it can cross the membrane.
  • Some substances are too large to cross the membrane.
  • Movement of materials occurs in both directions.
  • Water is the substance that most dramatically affects the volume of a cell.
This is a very simple way to get the basic concepts of osmosis and diffusion across to our biology students. Hands-on and highly visual is the way to go.

Other resources used in my teaching of cellular transport include the following. Click the links below to view in my TPT store.
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