In class I try to provide uniform coverage of the text with extra material to illustrate how astronomers use physical principles to interpret what they observe. Every lecture probes some topic on a deeper level than the book, but students aren't required to master the extra material in order to do well. Examples and homework assignments use lots of algebra, and include simple calculus later in the year. In the fall they observe the motion of the sun near the horizon on two dates and draw conclusions about the seasons. My involvement with PHY 205 has been as a lab instructor and leader of tutorial sections.
Tutorials try to stimulate clear thinking by solving problems.
While they're beavering away, or staring blankly into space, I visit each desk to check on progress, give encouragement, and offer hints. In this process I stress the application of physical principles and the advantage of developing a problem-solving strategy. One part of the strategy is obvious to a scientist but very difficult for a novice. This is to get as close to the answer as possible before switching from algebra to number crunching. Intuition develops slowly, but surely with practice.