"Many will be adding, not substituting, alcohol use with the use of weed." and where did you get this information from? I would also be curious to know and why/how you believe this?

"...it's much easier to smoke a joint during recess or before school and enter the premises all high."
Is it somehow harder now, that it's illegal? This is an outdated view though, besides, who said they need to 'smoke' it?