Tweaks

Who redistributes the skittles, teacher first then students.

Children only start to be 'out' after playing for a few times, or if they deliberately kick over the skittles.

Extension

Can extend by making the hoop sizes smaller (physical dexterity) or by adding more skittles up to around 20 with 5 hoops.
Can also say a number of skittles that the children have to stand in the hoop which contains that amount.