I'd suggest looking at the Terms and Conditions for nonprofit use, here is a screenshot of where it is on the webpage:
Look at this form that they link to for legal understanding of what they mean:
- NONPROFIT ORGANIZATION(S): A university or other institution of higher education or an organization of the type described in section 501( c)(3) of the Internal Revenue Code of 1954 (26 U.S.C. 501( c)) and exempt from taxation under section 501(a) of the Internal Revenue Code (26 U.S.C. 501(a)) or any nonprofit scientific or educational organization qualified under a state nonprofit organization statute. As used herein, the term also includes government agencies.
- The RECIPIENT and the RECIPIENT SCIENTIST agree that the MATERIAL:
a) is to be used solely for teaching and academic research purposes;
b) will not be used in human subjects, in clinical trials, or for diagnostic purposes involving human subjects without the written consent of the PROVIDER;
c) is to be used only at the RECIPIENT organization and only in the RECIPIENT SCIENTIST's laboratory under the direction of the RECIPIENT SCIENTIST or others working under his/her direct supervision; and
d) will not be transferred to anyone else within the RECIPIENT organization without the prior written consent of the PROVIDER.
All of this suggests to me that a high school would be fine, only wrinkle I can think of is whether they think that you can decontaminate any resulting materials (i.e. put it in a biohazard bag or bleach the hell out of it).