having grown up in an area with a bad reputation (high crime, high drug use, high teenage pregnancy, high unemployment) and lived in a similar area in London, I would say its not all bad.
I have found that these areas, while having alot of problems, also have a high community spirit and the people there form very tight knit communities. I have also found that with areas that have bad reputations, the media report only the bad stuff, you will hear about the crime, the muggings, the shootings, the burglaries BUT you wont hear about the neighbourhood projects , the charity events, the kids who come from bad families but grow up to be community leaders etc etc.
That being said though, while I have never been a victim of any sort of crime, I am very streetwise and aware of personal saftey, more so than my friends who grew up in more affluent areas.
It is possible that your daughter may choose to go to one of these colleges in "sketchy" areas, they may offer s specialised course or a very high standard course she is interested in. If that is the case, then be the be the adult and put her education first. Yes you will worry but you can prepare her for going to college in a "sketchy" area.
You can teach her about personal safety.
For example any handbag I own, is zip top and I carry it with my hand resting on the zip. I don't walk around with my phone in my hand. I keep my phone in my zip locked bag, not loose in hoodie tops or jeans pockets. When I go to cafes, bars and restaurants, I keep my bag on my knees or between my feet. I don't hang my bag on the back of a chair. This deters opportunist pickpockets.
When I walk around town, I am very observant. If I am walking down a street I haven't been on, I make a quick mental note of landmarks, buildings etc.
When I am public transport, again I keep my bag close to me, with my hand resting on the zip. I people watch, both out the window and other passengers, familiarising myself with the bus route and random passengers. For example, on my morning bus journey to work, I can recognise many of the passengers and know which stop they get off at.
I also keep an uncapped spray deodorant handy in my bag.
If I am out and about when it is dark, I always stay in well lit, busy areas. When I am out and about, I am very aware of my surroundings and noise and shadows. I never listen to my mp3 player when walking around, either during the day and especially not at night.
If I am public transport when it is dark, I stay downstairs (we have double decker buses) near the front of the bus.
Another trick I use if I am in an unfamiliar area is to research the area and map out my route on Google maps before I go to that area. Then when I get off the bus I know exactly where I am going and don't look like I have never been there before. Locals walk with a purpose and confidence, so that's what I do. I walk confidently and fast paced, like I have walked down that street hundreds of times.
I also try to dress like a local. One thing which really marks you out as a non local, and therefore a possible crime target is clothes. It used to be one of my favourite ways to pass the time while waiting for friends in London, spot the tourist. As someone who lived in London, I just wore my everyday clothes when shopping or meeting my friends in the tourist areas of London. It was really easy to spot the tourists cos they would be wearing their good clothes or holiday clothes!
There are lots of tricks like this, to make your daughter be aware of her personal safety and be streetwise. Also remember that "good" areas have crime too, its just not talked about as much as crime in "bad" areas!