REEDSBURG, Wis. (AP) — An elementary-school event in which kids were encouraged to dress as members of the opposite gender drew the ire of a Christian radio group, whose angry broadcast prompted outraged calls to the district office.

Students at Pineview Elementary in Reedsburg had been dressing in costume all last week as part of an annual school tradition called Wacky Week. On Friday, students were encouraged to dress either as senior adults or as members of the opposite sex.

A local resident informed the Voice of Christian Youth America on Friday. The Milwaukee-based radio network responded by interrupting its morning programming for a special broadcast that aired on nine radio stations throughout Wisconsin. The broadcast criticized the dress-up day and accused the district of promoting alternative lifestyles.

"We believe it's the wrong message to send to elementary students," said Jim Schneider, the network's program director. "Our station is one that promotes traditional family values. It concerns us when a school district strikes at the heart and core of the biblical values. To promote this to elementary-school students is a great error."

Schneider co-hosts "Crosstalk," a nationally syndicated call-in Christian radio show.

After the program aired, both the school and Reedsburg School District office were flooded with calls complaining about the event.

The response surprised Principal Tammy Hayes, who said no one had raised any objections beforehand. She said a flier detailing Wacky Week had been sent home with children the prior week, and an announcement was also included in teacher newsletters.

The dress-up day was not an attempt to promote cross-dressing, homosexuality or alternative gender roles, district administrator Tom Benson said.

"The promotion of transgenderism, that was not our purpose," Benson told the Baraboo News Republic. "Our purpose was to have a Wacky Week, mixing in a bit of silliness with our reading, writing and arithmetic."

The theme for Friday's dress-up day came from students, Hayes said.

"It's different every year. They basically present the ideas, and they vote on what they would like from Monday through Friday," Hayes said. "... They did not mean anything by this day. They were trying to have fun and come up with a fun dress-up day."

About 40 percent of the student body dressed up Friday, Hayes estimated, with half portraying senior adults and half dressing as the opposite sex.

"I can assure you we will not be having this day (again)," Hayes said.

Reedsburg is in southern Wisconsin, about 60 miles northwest of Madison.