AM at screaming point here! She's actually just 6 but takes an age 8.
She is one of these kids who has sensitivity issues about clothes. She will only wear stretch waist trousers (no buttons etc). However she will not wear what she calls " funky" trousers, i.e ones which flare or flap at the hem. These includes nearly all school trousers which are bootleg shape.
We got through last year with some velour jeggings from M and S, but they are worn out now.
All the adult shops are full of stuff called ponte in straight/skinny styles with pull on waist, but it apppears this hasn't infiltrated down to childrenswear.
Nearly had some in H and M , but they stopped at age 8, and not really long enough. So at the moment she is wearing leggings to school 
.
Skirts are not an option as this will mean a tights war. She is not the only one, I have been on several threads about kids with clothes issues.