This teacher's guide contains part two of the four-part first year Portland Project, a three-year secondary integrated science curriculum sequence. This part involves the student with unifying principles essential for deeper understanding of the concept of energy. Confidence in the atomic nature of matter is built by relating heat in terms of random molecular motion via the colorimetry experiment. The energy concept is then extended and generalized via various energy conversions, and finally, limitations and implications of energy conversion are explored, ending with a view of life as an organizer in nature, powered by energy, but always at the expense of influencing its environment. Notes to the teacher, examples of data, materials and equipment needed, and problem calculations are included. (SL)