Rather than speak out for a cause they feel is important, tens of thousands of students across the country were planning to spend their day today showing their support of gay and lesbians in schools by not saying anything.

Organizers of the National Day of Silence are hoping the message sent out by high school and university students rings loud and clear — even if nobody’s talking.

Nearly 2,000 junior high and high schools planned to participate, they said, including at least 64 in Missouri and 27 in Kansas — two states that have approved constitutional amendments banning gay marriage in the past eight months.

Students at nearly 700 colleges and universities across the United States also were planning to participate by going the entire school day without talking, according to the Day of Silence Web site.

The first Day of Silence was in 1996 at the University of Virgina, and a year later spread to nearly 100 colleges and universities.

The success of the Day of Silence has prompted conservative activists to launch a counter-event on Thursday called the Day of Truth, aimed at mobilizing students who believe homosexuality is sinful.

Participating students are being offered T-shirts with the slogan “The Truth Cannot be Silenced” and cards to pass out to classmates declaring their unwillingness to condone “detrimental personal and social behavior.”

The driving force behind the Day of Truth is the Alliance Defense Fund, a Christian legal group that has opposed same-sex marriage and challenged restrictions on religious expression in public schools. The event is endorsed by several influential conservative organizations, including the Christian ministry Focus on the Family and the Southern Baptist Convention’s Ethics and Religious Liberty Commission.

Mike Johnson, an Alliance Defense Fund attorney from Shreveport, La., said organizers were unsure how many students would participate in the Day of Truth, but expressed hope it would grow in coming years as more people learned about it.