*edited to add suggestions for lolly free bags, normally I add things like textas, if you have a label maker make a name label for each child and stick it on a grey led pencil, stickers, exercise book, little baked gingerbread freckle cookies in a bag, cookie on a stick, magnets, little pegs, in summer normally juice in a box (that’s a treat for my kids) anything really apart from lollies. 
I prefer a creative bag with baked cookies as opposed to a sugar high bag that will drive the parents nuts.