Gunnar, finding clad is no problem. You just have to find places that people gather, better yet where the kids gather. Check the picture I posted on the counter removal post. I found hundreds of coins in around 3 hours at the high school. But more inportant this is the spot were the kids load onto the buses. 1500 high school kids will drop a lot of coins. They actually throw the pennies away.
I hunt many tot lots, again another gathering place for kids. Here again not all places in the lot produce the same. I do better under the hanging equipment, I also think where did the mothers sit or stand. I'd rather find one ring than 100 pennies. In the same school field the kids baseball leagues practice. I look where the equipment bags are laid down, where the parents sit and watch, where the parents are getting their keys out for the cars etc.
Sports fields are good. I done well around the bleachers, the coaches boxes, dugouts, and the concession stands or drinking fountains. On soccer fields I check the sidelines first and behind the goals. On Tuesday I found several coin spills under some shade trees behind the backstop. They are the only trees on the field. The list goes on. The trick is to watch were the most people were or where they had reasons to go into their pockets. Rob