School project lead to undesired subscription - refund possible?

Your son had 14 days days to cancel his subscription without incurring any fees.  Looks like he failed to do it in time. 😞

At this point, the early cancellation fee is 50% of remaining months of service.   You can confirm how many months remain by logging-in below with your son's Adobe ID and password.  To avoid penalty fees, wait until the 12th month of service to cancel.

https://account.adobe.com/plans

===============
How do I Cancel my Subscription?
https://helpx.adobe.com/manage-account/using/cancel-subscription.html
===============
Subscription & Cancellation Terms:
https://www.adobe.com/legal/subscription-terms.html

CONTACT ADOBE SUPPORT:
================
Online Chat: https://helpx.adobe.com/contact.html?rghtup=autoOpen
Phone M-F, during normal business hours: https://helpx.adobe.com/contact/phone.html

Hope that helps.

possibly.  it's up to the adobe support person you contact.  having a non-oppositional attitude (like you've already displayed) is helpful.  also, be aware they're likely to offer you 3 months free (which still leaves you with paying for 12 months in exchange for a 15 month subscription).

using a browser that allows popups and cookies, contact adobe support by clicking here, https://helpx.adobe.com/contact.html?rghtup=autoOpen
in the chat field (lower right), type AGENT
be patient, it can take quite a while to reach a human

p.s. if you're contacted by anyone (via email or private message), it's much more likely to be a scammer than an adobe representative. ie, double check for an employee badge if contacted in the forums and look for an adobe.com domain in the email address if you click reply to an email. then check again and be very suspicious. any other method of contacting (or offering to contact you) is almost certainly a scam.

p.p.s you can also use phone (but chat is usually quicker), https://helpx.adobe.com/contact/phone.html