Singing on pitch is an important part of developing your singing voice. When I start teaching a new student, many times they slide up to the note, strain their voice to sing the note, or sing the note with no support of their diaphragm. They don't realize the importance of singing each individual note on pitch. Try this exercise to see if you can sing a note on pitch without scooping up or down first. Play a note on your piano, keyboard or smartphone piano app and try to match that pitch. Now, play another note and match the new note. Don't scoop up or down to the note--just sing it dead on to match it. Just think of a bull's eye and hitting the center of it. This takes practice. Most of us will sort of hit the note, then we adjust it. This is not what we are trying to do. We are trying to sing the note without adjusting or wavering our tone, and it is hard to do. It takes concentration. And the higher or lower the note is for us, the more we need to concentrate.
Scooping is a real problem in singing. We may think it sounds good to scoop, but to really does not. (Once we learn to sing our notes perfectly, then we can learn to scoop like the professionals. ) And when more than two notes are involved, most amateur singers just slide down the notes. Each note should be sung as individual notes--no running them together. This takes practice--over and over and over. The best way to hear if you are singing on pitch is to record yourself as you exercise. And when you sing those high notes, do not forget to use your diaphragm when singing the pitches. You will never match them correctly if you don't. When you are singing a 1-3-5-3-1 exercise, watch out for the 5 note! It will be flat if you do not concentrate. Try to imagine that you are an instrument. When played, most instruments hit the note as a pure note. When I am singing (especially in a group or choir), I try to picture that I am a clarinet or an oboe when I sing--especially when we are singing a section where blending is important. Just like an orchestra blends all the instruments together for one unified sound, so should we blend our voices together in the same way.