I learned Russian a while ago, but I'd like to brush up on it?I was at an intermediate level when I stopped but that was 3 years ago. I'm wondering how difficult it would be?

Hello! At my university I will have to do my 3 weeks practice now. I have never taught before and I will have my first lesson of Russian language in a high-school soon. I would like to do my best and not to bore the children as they are very motivated at the moment. I will teach 9th(beginners) and 11th(intermediate level) grade. I would like to ask if you have any ideas for some games, pair or group activities. Maybe you remember some nice methods from your school or language course. Thank you in advance!