For BOYS

Plain Formal Shirt (of light colour with full sleeves)

Plain Formal Pant(with two plates on both sides)

No Belt

Black Formal Shoes (with lace).

For GIRLS

Salwar Suit (with dopatta)

Simple Low Heel Sandal.

Moreover I will suggest you please go through their official website for once.

Hope you find it helpful

let me know in the comment box if you are having any further doubts

thanks

Good Luck!