I already congratulated you in the chat that your mom is accepting your decision to grow dreads, but I wanted to do so again! It really is a hair style that has a lot of stereo types associated with it that aren't necessarily positive ones. High school is definitely one of the hardest times of your life. Especially the cliches that are essentially clones of each other and make themselves feel better by ridiculing everyone else who is not exactly like them.
I'll be honest, when you grow dreads the natural way...your hair won't look good till about 2 years in! There will be times when you absolutely HATE your hair...you'll be frustrated that it doesn't seem to be progressing fast enough! But...often that dislike is not actually coming from you...but what society tries to tell you that your dreads should look like! They have this belief that dreads should be "maintained" and "manicured." But...just remember to keep rocking the crazy tangly mess....cause eventually you'll be rewarded with beautiful HEALTHY dreads that aren't a carbon copy of each other or every other salon dready.