Your school network sees an encrypted connection to the proxy domain — not the sites you opened. Your school's acceptable-use policy still applies to you personally.
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School networks (Cisco Umbrella, Zscaler, Cloudflare Gateway, and similar) log the domains you connect to but cannot inspect the encrypted contents of HTTPS connections unless the school has installed a corporate root certificate on the device (rare on school Chromebooks, more common on enterprise-managed devices). So the network sees you visited anyproxy.site; it does not see what you opened through it. The visibility of that visit varies by policy: some school MDM tools flag repeated visits to any single external domain; others just log everything without action; strict enterprise-education configurations may specifically categorise "proxy avoidance" domains and add them to block lists. Two important notes: (1) Your school's acceptable-use policy still applies to you personally regardless of what the network can technically see. If your handbook prohibits proxy use, you are bound by that agreement. (2) On a shared or borrowed school device, close the browser tab and clear cache after use so the browser history does not leave a local trail.
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