Pros
You get a paycheck bi-weekly. For the most part, supervisors are hands off.
You get attached to the kids you work with. You really care for them and want the best for them. You'll probably spend out of pocket for supplies and crafts for the kids that HGA will never know or care about.
If you have a morning kid before 12:00 and the surrounding school district is closed, you get a "snow morning."
(Usually) no week-ends.
Cons
No holiday pay. No paid time off. No sick time. No vacation pay. No benefits pretty much other than a paycheck.
It's stressful work with a high turnover rate. It's just the nature of the job. Your loyalty means nothing to the company.
Kids get sick all the time. Families go on vacation. You get sick from being around sick kids all the time. You don't get paid when a kid, you, or a parent cancels. It's not a steady paycheck.
Your schedule changes every semester to work with the students. You may work 8-12, then 3:45-6:30pm with a big gap in the day. If you live close in town it's not that bad, but if you commute more than half an hour, I'd say it's probably not worth it.
You have to drive kids around in your personal vehicle. This is a deal breaker for me, but not for most. Normal children in general are germ machines. Children with special needs are even worse atnot coughing into their hand, or shoulder, or just sneezing on any surface without reservation.
Since they make money off of you holding session with the kid, you feel guilty for wanting to take a vacation, time off, sick day, etc. if someone else can't cover for you.
Even if you do offer to cover for someone, there will be no gratitude. If you give an inch, they'll take a mile.