When and how is the best time to be asking for recommendation letters?

Answered

It's best to ask whoever knows you the very best at your school ASAP to consider writing a recommendation letter for you so ask before you leave for summer vacation. If they agree, then tell them that you will send them a reminder a couple of weeks before school starts when the Common App or the Coalition App opens up.

Regardless of your intended major, your intended merit, or financial need-based scholarships, you always want the pick people who can communicate effectively with great command of the English language to advocate for you.

It is a mistake to pick the most popular teacher or the one where you know 15-25 other students are going to ask them for recommendations. Why? Because unless you know you are their very favorite pupil who has contributed the most in the classroom, in and out, you are just going to be the #8th or #15th ranked recommendation from that person and that will do very little to convince admissions officers that you are a remarkable human being.

Rather, pick someone who you trust, knows you well, and that you can rely on to give a glowing report of who you are and where you are going. This person can be the lunch lady, the custodian, your tennis coach, or the vice principal, it doesn't have to be Chem teacher because you want to study Chemistry. The caveat is that some schools like CalTech or MIT, specify that they want 1 STEM teacher and 1 humanities teacher. Therefore, carefully read all college application requirements when you apply.

Some people may disagree with this or having the same people write your recommendations for college and scholarships but I personally think these institutions are looking for the same qualities in their successful candidates.

Good luck.