What all should my cosmetic bag consist of when in 6th grade?

As mentioned you are a school girl i would suggest you to carry a small vanity bag in your school bag.A vanity bag with multiple pockets so that you can easily carry your cosmetic products.These bags are easily available in market or you can buy them online.As you seem to be fond of makeup and good looks i would suggest you the following products which you must have in your vanity bag

Concealer: if your skin demand

Foundation it will bring additional glow to your teenage skin

Blush

Eyeliner: maybelline is good to opt.

Mascara : maybelline 's is good and can be used.

Eye lash curler must have one

Eye shadow: sephora eye shadow are good

Light pink or clear lip-gloss again stila is good

You should also not forget to keep

Sunscreen

Soft tissue paper

Hair brush

A compact mirror

and a deo

In winters a Hand cream and a Moisturizer(from stila) should be added in the kit

but you should not use all products on a day- to-day basis.on daily basis you can use moisturizer with mascara and lip gloss.These products will enhance your natural beauty and bring out best from you.I would suggest use the makeup to bring out your natural features rather than mask them.