A "perfect storm of events" led to an impossible demand for substitute teachers in Kamloops this month.

It's a situation that could compromise students' learning experience and overburden teachers with work, said Jason Karpuk, Kamloops Thompson Teachers Association president.

Karpuk has asked the school board to take a look at the substitute teacher numbers. But he acknowledges that it's a fine balance since too many substitutes means fewer working opportunities for each one.

"I think they're trying to maintain the (teacher on call) list but I think we really need to sit down and look at what those numbers are," he said.

The issue came to a head last week when several events collided, according to Supt. Terry Sullivan.

At a time when districts traditionally have the highest illness rates, Kamloops also hosted a provincial basketball championship that involved several teachers and the district held a training workshop that took 45 teachers away.

An average of 90 substitutes were called each day last week, according to John Churchley, the district's lead on human resources.

Also adding to the problem is that of the 250 on the substitute list only about 110 are actually available since by this time of year many have attained permanent positions.

"That's also part of the perfect storm," said Churchley.

Sullivan said this year is no different than others.

"That happens to us from time to time and when it happens we have principal and vice principal and non-enrolment teachers that fill in," said Sullivan.

However Karpuk said this is an inordinately challenging year for on-call help.

He supports the use of school administration as a better alternative to another option — pulling learning assistant teachers or librarians from their specialized work.

"These are students that we've identified as being at risk and needing additional assistance and if they aren't getting it because that teacher is being pulled it means it's adversely affecting their educational program," said Karpuk.

And when the frantic search for a substitute leads to a last-minute parachuting-in of an unprepared teacher, it can also undermine the quality of that day's lessons.

"Your room isn't always set up so that it's obvious what you're going to do," said a substitute teacher who did not want to be named.

"You're scrambling to be on top of things. Usually the kids are pretty good and the rest of the people in the building are pretty good. But that's where having a bit more experience is helpful."

The district decides on-call teacher intake in the spring and adds to it in the fall. The KTTA has asked the school board to review and possibly increase those intake numbers.