Help a CS Teacher decide: Keep Plus or switch to Claude/Gemini?

Hey guys, I've been on the ChatGPT Plus since the beginning, but as a CS Teacher, I'm starting to wonder if the grass is greener elsewhere. I use it daily to prep lessons, answer general questions, and do some coding work (mostly small scripts or very small projects). Are there better services in the $20 USD range right now? I keep hearing about Claude's superior logic and Gemini's massive context window (which seems great for uploading whole curriculums). A friend is Claude Pro evangelist, but he owns a business.