I don't know the answer to your question about college courses, but I can confirm that Carers Allowance has always been considered a 'benefit' in the same way that the State Pension is considered a 'benefit' !
Re your first question I'd suggest contacting the Carers UK Adviceline team - they are the acknowledged experts on all matters related to caring and benefits
Need expert advice? You can talk to the Carers UK Adviceline five days a week, no matter where you are in the UK or how complex your query is. We do benefits checks and advise on financial and practical matters related to caring.
0808 808 7777
Open Monday to Friday, 10am to 4pm
The Carers UK Adviceline also includes a listening service, there for you to talk through your caring situation with a trained volunteer who understands what you are going through. Available Mondays and Tuesdays, from 9am to 7pm.
If you can’t get through on the phones (lines are often oversubscribed) then send them an email, they’ll usually get back to you within 3-5 working days.