The BEST!Keeps the shin guards in place, provides some protection to the outside of the leg, and the ankle ball joint, and is a cloth barrier with the shin: http://www.storelli.com/soccer-leg-guard
These actually worked for my DD:
https://www.amazon.com/Silver-Lined-Guard-Soccer-Model/dp/B012W70AVM
And, my DD and her teammates rarely wear shinguards at practice. They only put them on if they are going to be having a scrimmage.
What happened to "practice like you play"?
Try telling that to 15-18 year old and college players.
I assume the coach will tell them.