Class sizes at Riverside-Brookfield High School have increased by an average of two to three students this year over last year, as budget cuts have reduced the number of teachers and limited the number of class sections.

But averages can be misleading, as there are now more than 30 students in nearly a quarter of classes at the school.

According to a report presented by District 208 Superintendent Kevin Skinkis at the Nov. 13 meeting of the District 208 Board of Education, the average class size in non-laboratory classes is 26.36 students, compared to an average of about 24.31 students last year.

This excludes fine arts and physical education classes, which average about 40 students per class. The average class size number is also brought down by English as a Second Language (ESL) classes, which average only 12.83 students per class.

This year lab courses – science and applied arts – are averaging 26.64 students a class, compared to a little more than 23 students last year.

The size of the faculty has been reduced by the equivalent of 8.6 full-time positions, and class sections were cut by about 7.4 percent this year and are down more than 17 percent from the 2010-11 school year.

There are more than 30 students in 93 of the school’s 414 classes (22.4 percent) this year.

RBHS has 54 classes with 31 or 32 students, 26 classes with 33 or 34 students, 11 classes with 35 or 36 students and two classes with 37 or more students this year. The school also has 25 classes with less than 20 students.

The class-size goal is to average about 30 students in academic non-laboratory classes and 26 students in lab classes, Skinkis said.

Two classes with 37 students are a health class and an economics class, according to Principal Pamela Bylsma. There are five academic classes with 36 students, including two sections of economics, two health classes and a geometry class.

In addition, there are six academic classes with 35 students: two sections of Spanish I, an economics class, a western civilization class, a U.S. history class and a health class.

English classes this year average 28.51 students, an increase of almost four students from a year ago. That increase makes a big difference, according to Sarah Johnson, the chairwoman of the English department.

“It’s hard to build relationships with students when classes are so large,” Johnson said in an email. “We are especially concerned with the impact to our freshmen. Because of their need for more targeted instruction in their adjustment to high school, teachers worry that their experiences are being jeopardized.”

The close interaction between teacher and student, which has been a point of pride at RBHS, is jeopardized by larger class sizes, and teachers are concerned, Bylsma said.

“During the class period each student gets less individualized attention as the number of students goes up,” Bylsma said in an email. “The challenge with that reality is that our teachers have always prided themselves on providing targeted assistance in the moment of need for our learners. That is compromised as the class enrollments goes up.

“[Our teachers] have a standard of performance that they value highly, yet they cannot achieve it at the same level or with the same quality as in the past. The level of frustration and concern that engulfs them can be overwhelming at times. It is a difficult adjustment for the teachers to make.”

Math classes average 25.82 students per class, while science classes average 26.55, and world language 26.17.

Social science classes have most crowded classrooms among academic subjects with 29.79 students a class. Non-laboratory applied arts are also much larger this year, averaging 35.5 students per class compared to about 22.4 students last year.

The school board cut staff as it made budget cuts after the defeat of a tax referendum in 2011. Last year, RBHS had a faculty of 94.5 full-time equivalent (FTE) positions. This year, the faculty has been reduced to 85.9 FTE’s.

Skinkis says that he would not want class sizes to get any larger than they are now.

“We shouldn’t go be trying to go above 30 to 1,” Skinkis said. “If anything, you would like to hang around right below 30 to 1 in all our classes and we have some that are over that.”

Skinkis said the school will probably need to hire more teachers next year just to keep pace with increasing enrollment and to maintain current class sizes.

“We’re going to increase our current staffing by about two teachers,” Skinkis said.