Teacher recommendations from multiple schools?

<p>I currently go to two different high schools to take both core and extra curricular classes. One of these high schools is considered my "home" or "main" high school, while the other high school takes in students from multiple schools across the district to allow more students to take a wider range of advanced classes.<br>
Because the Common App only allows me to enter in one high school (that I can see), is it possible to submit teacher recs from other high schools as well? If so, would these teachers have to send in written recommendations to each college through the mail instead of one recommendation submitted electronically?</p>