FOSS WAVES textbook pages 33-39

NASA Electromagnetic Spectrum

BYJUS- Electromagnetic Spectrum

Britannic Electromagnetic Spectrum

When a photon of light hits an electron, the photon transfers some of its energy to the electron. If the photon has enough energy, it can excite the electron, which means that it can raise the electron to a higher energy state. In other words, the photon's energy can be absorbed by the electron, causing the electron to move to a higher energy level within an atom or molecule. In the case of Lithium, when the electron returns to its ground state, it will release that energy in the form of a RED photon of light. 

Fizzics.org

You can create a similar diagram like the one below on the back of your Foldable.