This document contains summaries of 4 lessons:
1. Waves, including wavelength, amplitude, frequency, and types of waves.
2. Sound, including how it is produced, travels, is measured by pitch, intensity, and decibels.
3. Light, including reflection, refraction, absorption, and how materials interact with light.
4. Heat transfer, including temperature, thermal energy, and the processes of conduction, convection, radiation, infrared, heat sources, and energy transfer.