Picturing to Learn is a database of hand-drawn visuals by college science students prompted to explain a science concept to a high school student. These visual creations are a powerful way for revealing student understanding.

The following text is from the Picturing to Learn site:

The Picturing to Learn program was founded on the following core premises:

• drawings made by science students for the purpose of teaching others reveal misconceptions
• those drawings provide teachers with direct feedback on what students are and are not “getting,” to help promote more effective teaching
• the process of creating a drawing to teach others has the potential to deepen students’ understanding of scientific concepts

You can register for FREE which gives you access to over 3000 examples of student thinking on topics such as Particle in a Box, Brownian Motion, and Cell Generation & Membrane Potential.