"Go by the board" means that something is lost, forgotten, or abandoned; it's a type of figurative expression known as an idiom. Idioms are phrases that are commonly known in certain areas of the world, but they might not make sense to others. An idiomatic expression can't be interpreted using the literal meanings of the words. The sides of a ship are known as boards, and "go by the board" actually originated as a nautical expression. It refers to being thrown or falling overboard, and is often used when discussing things that have ended or no longer exist.
When an item is lost, or when an activity has been discontinued or abandoned, the phrase "go by the board" can be used to describe that condition. An example is a student saying that his or her favorite activities have to go by the board during exams. Another possible use of the phrase would be saying that a possession has gone by the board when it is lost or broken.
Since it was originally a nautical expression, the phrase "go by the board" began to be used in the English language during the 1600s. The decks and sides of a ship are called boards. The first uses of the phrase were referring to instances when the mast fell on the deck, or when something went over the sides of the ship. It isn't known if the phrase originally referred to falling on deck or going overboard, but it was used in both ways in written nautical accounts of the era.
Later on, the expression began to be used to refer to things that were forgotten, abandoned, or lost, as well as discontinued activities. This idiomatic translation of the phrase "go by the board" was used from the 1800s until modern times. It is used both verbally and in writing to refer to a variety of situations that have ended, along with items that are lost or no longer exist.
Like many idioms, this expression is commonly known in certain English-speaking areas of the world, but it may not make sense to people in other places. Even when a person knows what the individual words mean, he or she often won't be able to make sense of an idiom unless it is explained. Idioms add an interesting flair to language, and are often very evocative of their meanings for those who have the necessary background knowledge. For someone who is not familiar with these phrases, or who is learning the language, they wouldn't make sense because the meaning has very little to do with the literal definitions of the words.