I was asked to do a Harry Potter show about 8 or 9 years ago; actually, I was asked to do a show and was pretty much told at the show it was a Harry Potter theme. At the time, I had never even heard of Harry Potter, so I did my standard program surrounded by lots of kids wearing black plastic John Lennon glasses...
My props that are dealer-bought were chosen for their quality, such as Steve Dick's "Superior Hydrostatic Glass", while my self-made ones in some cases make the prop actually workable (removed the Soft Soap gimmick from the unuseable included thick cotton rags with fake lipstick marks and substituted Abbott's silks that I then spray painted to suit my own needs).
I also sold a slew of not-being-used props on ebay that ended up getting me very little, and to be honest, they probably sold for what they were worth. Either flat-out got rid of or completely upgraded to materials and workmanship that will last for a lifetime of use.
Another issue was the children's magic videos I had that I also sold for pretty much nothing. What I really learned from them was how NOT to do a children's show, since most of the time, the audiences looked completely uninterested while the magicians themselves were either unsmiling and mumbly or overly unctuous. I already had my own style, wanted to see what else was out there, and discovered I'd rather continue to have my own style.
A major source of guidance has been Denny Haney, who I immediately felt a kinship with when I first visited his shop because he had a bunch of DVD's, a few displayed tricks and two floor-to-ceiling rooms full of books. The John Booth books, "Forging Ahead In Magic" and "Marvels Of Mystery" have been great resources, as well as books like "Roy Benson By Starlight" which gave me the A-HA! moment in the way I did magic. The one DVD that I actually love is the Bobo disc that includes his elementary school show, which was the first A-HA! before the Benson book.
I think the children deserve to see programs that aren't what 99 out of 100 other magicians are doing, and sometimes I feel like I'm in the minority. There's more to children's magic than the "Me, Too!" Franchise that seems to pervade the field (in other words, go to 100 children's magic shows around the country and you'll likely see most of the same tricks done the same way with the same gags, with a consistency that would make McDonald's proud (McMagic, as it were).