"When you hook up with one bring it almost to the ice and then let it run, they always try to get back to the school so watch which way the line goes and you will know the direction the school is moving."
Interesting tip!
During open water I have caught fish and "jugged'em" by tying a long length of line to a balloon and then follow the balloon to stay on the school.
I don't think we are far from the age of having pocket transmitters and receivers to electronically tag fish to stay on the school..Ya never know!
Anyhow, perch are a fairly easy fish to catch...Usually. Keep moving and don't waste time on unproductive holes...This is where a flasher can save you a huge amount of time.
There is an old saying " Big moves find fish, small moves catch fish." Look for transition zones like islands, points, weed lines...But don't overlook the basin either. Also, I like to look for trees that have fallen into fairly deep water.
I like to start using a fairly heavy jig (pimple, rocker, rapala, etc)..until I get some action then if the action slows, drill a series of holes in the area and possibly downsize..Hard to say without a flasher to see what is going on. I am a firm believer in bait (mealies, wax, spikes) over plastics. Let your jig drop to the bottom then raise the jig a few inches to a foot off the bottom. If you do get into fish watch to see if the fish is spitting up any bait and look down its throut. It is not uncommon to recover a fresh or partially digested herring etc.. I have smeared my jig in the regurgitated bait and done very well with that..Especially on perch and crappies. Also, I frequently take some fatheads with me in a ziplock bag. No water, just fresh fatheads in a bag. The bait dealer may think your goofy, but I hate carrying a bait bucket with me and fresh dead on a jig works just fine and kept cool, you'll be surprised at how long those little buggers can last!
Be patient, keep moving and good fishing!...If you are tip-up kind of guy: Please ignore the for-mentioned!