A report released this week has found that some schools in the US state of Colorado are considered “hostile” environments for LGBT students.

The Gay, Lesbian and Straight Education Network (GLSEN), released a statement saying that, while some progress had been made across the US since it began studying school climates fourteen years ago, “much work remains to ensure that all Colorado schools are safe and affirming environments for LGBT students.”

Findings from the study found that LGBT students in the state face “high levels” of harassment based on their sexual orientation or gender expresson, and regularly hear anti-gay slurs from students and staff.

The GLSEN’s School Climate in Colorado report was taken as a snapshot of the experience of thousands of Colorado’s LGBT students, collected in 2011 for the National School Climate Survey.

The study did find that “most” students said they knew at least one supportive teacher, however “very few” said they had access to LGBT resources or curriculum.

90% of respondents said they regularly heard homophobic remarks, and more than half of students who responded said they had been physically harassed because of their sexual orientation.

Poudre School District, in northern Colorado, last year received the highest rating possible from One Colorado’s statewide survey of school district policies protecting LGBT students. Its policies state specifically that LGBT students are protected form harassment, discrimination and bullying.

Some schools based in Colorado have gay straight alliance clubs which aim to promote an environment of inclusion, and to stand up to bullying based on sexual orientation.

In a historic day for the US state of Colorado, Governor John Hickenlooper signed civil unions into law on Thursday, following several attempts to pass the legislation in recent years.