The poskim are divided on the reasons for prohibiting electrical apparatuses on Shabbat and Yom Tov.
Some prohibit them because they produce heat and are therefore similar to fire. Since this reasoning does not apply to to LEDs, the question of their permissibility on Shabbat and Yom Tov arises.
Sources for this class are available through the links in both WORD format and pdf. In class we will translate and explain these sources.