the only ones i don't remember were the chewing gum and the fort apache toy.
as i remember it, oly-oly-oxen (we said 'ox)-free was used in some games where all the kids had to be found, like hide-n-seek. those kids were 'out' but the 'it' kid had to keep looking until everone was found. while the 'it' kid was looking, one of the hiders could run out of hiding and tag the 'it' kid and yell oly-oly-ox-free. that meant the kids that had been found already were free to hide again, and the 'it' kid had to start over. the kid who tagged the 'it' kid, was taking a chance of being seen before the tag was made. so he had to sneak up from behind.