Perhaps you're a high school student who plans to go on to college and major (or minor) in music. Chances are that you play piano, and maybe a wind instrument. Maybe you've also done some song writing or arranging. You think that you're entirely prepared to make the jump to a college music program. But there is one area that you may be overlooking, sight singing. If you're not in the choir, or your school doesn't offer sight-singing instruction, you may be in for a rude awakening.
That was my situation. I had played some piano and a lot of clarinet. I knew rhythms and basic music theory. But I had never done any singing. When I got to college and was told that we would learn to sing any of the parts of a four-part chorale, I nearly panicked. It seemed like magic. But I didn't need to. Needless to say, I learned it. But I'd have been a lot happier if I could have developed some background in the skill before college. Then I would have been ahead of the others in my class, and would have made a first impression as an accomplished musician. But I didn't. Maybe you can get it right where I got it wrong.
Sight singing is very different from playing an instrument. For an instrument, you actually need a much higher level of musicianship. You have to know the names of the notes that you are playing, so you can match them to the fingerings that you've learned. You have to know whether the notes are sharp or flat or not, so you can adjust the fingering accordingly. None of that really matters much in singing. But the skill of hearing is what's missing. If you use a certain fingering, you know a certain note will come out. There's no need to imagine the pitch before you play it. But in singing, you are the instrument. You have to know the pitch of the next note; there is no fingering to help you. It's a totally new skill.
On the other hand, you have a lot of the knowledge that you need already. You have a good knowledge of rhythms, something many singers never acquire. All you need to learn are the note pitches. And that knowledge is really easier to acquire than you might think.
There are basically two skills that you need to learn. One is to identify "Do", the tonic note, both aurally and on the sheet music. There are some simple rules to find it on the staff. For example, in keys with multiple flats, the second flat from the right in the key signature indicates the note that is "Do". As far as hearing "Do" is concerned, once you realize that virtually all songs end on the tonic note, you can get used to hearing and identifying that note throughout the song. Just imagine that if the song ended on that note, would it feel complete? If so, that note is probably "Do".
The other skill is learning the way the other notes sound in relation to "Do". Each of the other notes of the scale is a specific interval away from "Do". You can practice jumping from "Do" to each of the other notes. Once you've gained confidence with that, you can practice jumping around between the other notes without returning to the tonic. Once you can connect these various note-sounds with the notes on the printed page, you've come a long way toward being able to sight-sing with proficiency.
If you can develop the skill now, while you're still in high school, you'll be able to impress the professors and the students when you get to college. They will recognize immediately that you are student who's a couple of steps ahead of the others. That's not a bad reputation to have. It might even make it worthwhile putting in some extra effort now to make sure it happens.