Interesting topic and I have been asked this a lot over the years.
High school: I guess it was in LL parents would comment that he would play in high school. Son just played " differently" than other players and it was the one and only thing he could/would focus on. Our county doesn't have middle school ball, however, 8th graders can try out for high school JV ball. He made the team and started at JV as an 8th grader. He was set to start Varsity as a 9th grader until a D1 commit transferred in to the school as a senior. Oh well, he knew his place, and he got called up later in the season.
College: Son played on a college showcase team in high school so the expectation was that the players wanted to play somewhere at some level in college. The summer between sophomore and junior year of high school several of his teammates were committing, some to his "dream school" and some to his runner up. The spots were filling fast (infielder). He was getting lots of looks, and unofficial visits, but no offers. Then......an offer! Instate! He took it. His one and only offer....but they really wanted him. He started as a freshman and played every game except one when he had a fever.
Pro: Son didn't tell me at the time, but he was getting on-campus interviews and asked to fill out the forms for teams (I think all but 2 teams asked for his information). He had several psychological tests. We would see the same scouts at games, but there was a LHP tranfer that they were looking at. Son played at a mid-major college so I (and he) knew it would be tough, but when the mid-major plays against some heavy duty D1s in the south and son hits a triple against a highly scouted pitcher, the scouts took note. He also had a great summer season in the Northwoods League and was co-MVP of his team. Then son told us a crosschecker was at a game. It got interesting when he got the paperwork for his eye exam, and a little more real when he got called over at his conference tournament for a urine test. I didn't believe he would actually get drafted until his name was called. Son couldn't pack his bags fast enough.