Late deliveries are causing widespread dissatisfaction with the National Library's new service to schools, the School Libraries Association says.
The library said it was providing books within four weeks of receiving schools' orders, but school librarians and teachers said the books often arrived too late to be of any use.
Some teachers described the new system as a travesty and a joke and some said they had stopped using the library at all.
The system of loans to schools was changed at the start of this year despite opposition from many teachers and principals.
The National Library stopped allowing individual teachers to order books and instead allowed schools to make one order per school term of books to support topics of study and others to support an interest in reading.
President of the School Libraries Association Miriam Tuohy said some schools were happy with the service, but others complained that their loan requests arrived late - sometimes too late to be of any use for the unit of inquiry for which they were requested.
"Where we used to get things almost immediately, now there's a wait of some weeks for anything to arrive," she said.
"Some schools it's all gone swimmingly. The earlier they've put in their order the better. Some have received a good number of books that are a good match and there's plenty of them, and other schools who have had to wait so long that the unit of inquiry that teachers were working on has been and gone and effectively it's too late by the time those books have arrived."
Ms Tuohy said there was widespread dissatisfaction with the new service.
"Lately it's been the delivery times which I know National Library have tried to address. But there's also schools are having some concerns with how up to date the resources are that they're receiving, what physical condition they're in, where some of them are quite old and tatty."
Teacher Melanie Dorrian ran an online poll of teachers about the National Library earlier this month.
She said nearly 200 teachers responded of whom 116 said their orders arrived "way too late" and four said their order did not arrive at all. Only five said they had no problems with the service and their orders had arrived as requested.
Survey respondents' comments included:
"I used to use it all the time with the old system. Don't use it all now because it's too hard."
"Our entire school (14 classrooms) cannot get any books until next year now because our coordinator sent off an order for one class. Once your school order has gone in that's it. It cannot be reopened. I tried to put in an order yesterday for four classes but found out we're too late."
"Hopeless. Book arrived far too late to be useful. First time I've just left them all in the box! What a waste of time for our staff member who coordinated and me filling out all the new criteria. Very unhappy."
"It was useless. I put in an order and so did another teacher - they sent a puny number relating to the topic and there was nowhere near enough to share. I've ended up leaving them all in her room. At least one person might as well get some use out of them."
Ms Dorrian said some teachers said their orders did not arrive until seven or eight weeks into the school term, by which time they had finished teaching the subject the books were for.
She said the library's former school service was efficient and had helped her discover books she would never otherwise have found.
Ms Dorrian said teachers were worried the service was being deliberately run down so that teachers would stop using it and it could be phased out.
"We need it reinstated back to how it was, because it worked for teachers," she said.
National Library director of literacy, learning and public programmes, Geraldine Howell said the library had provided services to schools for 75 years and intended to continue doing so for a long time to come.
She said the new service was still bedding-in, but delays in some schools' loans were disappointing.
"It can be up to four weeks before they get the resources. That is partly because we're at a distance from schools. We are serving schools from one end of the country to the other."
Ms Howell said it was trying to send orders out more quickly, but schools needed to make sure they made their orders in good time.
"Some of it comes down to planning. We do the requests in the order that they come in, so those schools that are planning ahead are getting to the front of the queue and getting their resources."
Ms Howell said the library was getting good feedback on the quality of the resources being sent to schools and said the new lending model was aimed at getting more books to more schools, especially low-decile and rural schools.
She said 65 percent of schools had registered for the service and so far this year the library had issued more than 250,000 items.
Ms Howell said schools used to pick up their book orders from a depot, but the library had negotiated a delivery service that sent books directly to schools for no more than $10 per box of books.