Monday night through Wednesday is Rosh Chodesh, the beginning of the interpolated 13th "leap" month of Adar A
(which precedes the 12th month of Adar B!) in a "pregnant" year ("Shana M'uberet" - see articles 1-2).

The name of this week's reading, Teruma," refers to the donations of materials for building the Sanctuary (see articles 5-6).
Today the word is used, like "tzedaka," to refer to all giving to worthy Jewish causes.