AHSEC HS Book PDF Download: Arts, Science, Science Stream E-Book@ ahsec.nic.in: Among all the resources that students need to prepare for the final exams, textbooks are the most important. We have put together a collection of Assam Higher Secondary Education Council (AHSEC) Class 12 Textbooks for Arts, Science and Commerce Stream. AHSEC HS Books 2021, Assam Board 12th Textbook 2021 Pdf Download. AHSEC HS Books 2021 Pdf Download link available in this page. Assam 12th Book 2021-2022 State Arts, Commerce and Science courses online from Assam Higher Secondary Education Council, Guwahati AHSEC website and NCERT portal have been provided online to students of English and Assamese medium textbooks for Class XI and XII of the Higher Secondary Course in the 2021 academic year.