I had Devon draw the part of the eye - as a means to have her full attention during our discussion about the brain processing sensory information. She was happy to draw the shapes as I directed, but was more concerned about her artwork, than the lesson. Once the lecture part got underway, she started to clean the wall of her room as we spoke. So the lecture turned to one of concept, rather than anatomy. We spoke about how inside the eye the is a water solution that also contain some salt. She was curious about why we have salt in our bodies, but cannot use the salt water from the oceans. I they started to explain a membrane and osmosis as a means for cleaning water. The idea that a more dense solution will flow towards a less dense solution seemed to be hard for her to understand. I tried to use the idea of a vacuum and how air will flow into a vacuum bag instantly. This lead to a brief discussion about how a jar could have nothing in it - not even air. We talked about how outer space is a vacuum, without air - but she had a real difficult time in grasping the fact. She asked about the planets and meteors and where they came from, in that vast empty universe. I again described the big bang theory - and was adamant that if we cannot know how the universe was made - why bother to study about it? We had a very nice and deep conversation about all of this, until she could hear no more.