Yes! Office 365 has always been available in a free edition for schools. The A1 license is completely free for both students and teachers, and offers full access to Teams, as well as web based versions of Word, Excel and other office tools.
If a school wants to move to an A3 or A5 license (for example in order to have the option to install Office applications for offline use), schools normally only pay for licenses for their full time staff : all student licenses are free of charge.
https://www.microsoft.com/en-au/education/products/office