"I heard that knights should be developed before bishops. Is that something my chesskid needs to follow? If so, why?"
Interesting question! It is true that there is a saying "knights before bishops." This could almost fall into the category of general principles, such as "a knight on the rim is dim," "develop your pieces and control the center," or "don't move pawns around your king."
There are many general principles in chess, and they help guide players in their decision-making. But...general principles all have exceptions. There are many instances where a move like Na5 has won the game, despite breaking the "a knight on the rim is dim" principle. Part of being a good player is knowing when to break these principles!
The "knights before bishops" rule is barely even valid. While there is very good justification for, e.g., being careful about moving pawns around the king, I don't think the knights before bishops rule holds true nearly as often as other general principles.
The justification for this saying is that it is more likely that you will know the best place for a knight before you know where a bishop should go. For example, lets look at the following position:
I managed to get this already quite rare position after only two moves in a last round game from a tournament which was held in a castle in Italy. Of course, White should develop a piece, but which one?
White could develop the bishop from f1, but do we really know where it would be best? Maybe it will be good on b5, c4, or even g2. Depending on how Black plays, the best place for the bishop might vary. White could also try to develop the bishop from c1, but should he play d3 and develop it on, e.g. e3, or maybe play b3 and fianchetto it?
These things we don't know yet. We might want to wait to develop it when we know more information. But, what do you think is the best place for the g1 knight? That's right, f3 is almost certainly its best post. It is actually hard to imagine a scenario where we would not want the knight there. So I played 3.Nf3 here.
This is the reason for the "knights before bishops" principle. It is often (although certainly not always) easier to determine their best location, than that of bishops. Also, the way the game above continued illustrates another reason: my opponent played 3...Nc6, and I pinned the knight with 4.Bb5. So, sometimes if you wait to develop your bishops, the possibility might arise that you can pin your opponent's knight with your bishop.
But in reality, this rule does not hold true very often. There are many, many exceptions. Even in the above position it is not clear that 3.Nf3 is best - the immediate 3.Bb5+ is interesting, meeting 3...Nc6 with 4.Bxc6+, forcing Black to double his pawns.
So basically I would suggest that your chesskid not worry about this "knights before bishops" principle. I would suggest an alternative principle: "Make the move you know you will make eventually, first!" For instance, if you are in the opening of a game and you are not sure whether to develop a knight to c3 or d2; or a bishop to b2 or g5; but you know 100% that you are going to castle in the next few moves - then you should castle right away. That way, you would keep all options open for the development of your other pieces. Then you could decide later, depending on how your opponent plays, how to develop the knight and bishop. This is called the "principle of flexibility".
Dealing with general principles - being able to decide when they apply and when there is an exception - is one of the hardest things for both the chess player and chess coach. You do need to know them and use them as guideposts, but you must also take them with a grain of salt, since there are many exceptions. The general rule of "knights before bishops" is even less applicable than many other general principles. It is worth knowing, but certainly is not something the chesskid needs to be worrying about. Instead, he should try to make the most flexible developing moves.
Thanks for reading, and you can send in questions about your "Chess Kid" to [email protected]