Since I was just on her looking for info on camping in Wasaga, I figured I'm probably not the only one so I'll toss in my two cents - even if it is 2 years later.
We usually stay at Gateway, which is on Main Street near the Walmart and it's decent. They have a heated pool and clean washrooms (I should mention that while I was fine, my husband is still complaining about how little water you got for the money in the men's shower). The sites (for tents mostly) are quite small and close together without much privacy but it's friendly, well taken care of and safe. They have a huge gate they close at night to keep the partiers from the campground down the road from drunkenly wandering in by accident but it's not locked so you can come back late yourself, if need be. It's about 55$ a night.
There is also Holiday Park campground, again on Main Street, which is family oriented and seems safe and clean though we haven't been yet (we are definitely going there this year). They also have a pool and washrooms and small sites. They are 45$ a night and you can get 3 nights (not weekend) for 70$.
Sunshine Park is on the same street but it is for 16 years and up only and is the party campground on that street. Beyond that, I know little about it since we are not the partying type (and now have a toddler).
We stayed at Jell-E-Bean campground last year and while it was family friendly (pool and playground) and the owners were nice, it was more out of the way and not as clean. The washrooms were ok but had trailer style toilets (instead of flush) and when the soap container got emptied, I found it lying on the counter full of dead bugs. They also allow pets and there was a huge dog mess right on the edge of our campsite that no one ever came to clear (to be fair, we didn't ask, but we thought they would check the site out when our neighbors left). I believe it was a little cheaper than Gateway, but in my opinion, not really worth it due to being farther away and not quite as nice. The playground is a nice feature. The showers were decent though (water pressure and length of water per quarter).