I've done the consignment thing and it worked okay cause it's little work and you get the cash when you want it.
But you would make more selling them on ebay in groupings of a couple outfits at a time or a few shirts together or throw in a pair of shoes.
But both of those options...you have to sell the clothes that are in season. My consignment shop won't take things that aren't in season.
I had HUGE success with a garage sale. Girl's clothes especially sell good. I priced my clothes the same as the consignment shop and people payed those prices cause they were good quality clothes from name brand places. Also, I spread the word through craigslist and facebook, and I had lots of friends of friends come cause they new what size clothing would be there and some of them spent $50-$100 at a time.
I know it's a lot of work but once it's all together, you could run the garage sale at two or three different times & locations throughout the summer.
If you're not up for that, I would definitely put the time into ebaying:)