Rudiments can be a great learning tool for any drummer. Instill in your student the need to learn rudiments and to continue to practice them. It's not about just learning them and moving on, but learning them and continuing to play them. Rudiments build up technique and skill, and also can be a good warm-up before a performance. Rudiments include the double-stroke roll, five-stroke roll, single para-diddle, flam and more.
While learning rudiments, exercises and songs can be beneficial, it's also good to just jam and be creative on the drums too. Make sure that's a key part of every practice session or drum lesson. Let the drummer be creative for a few minutes. This usually means letting them play a drum solo that they create on the spot. This will not only be fun, but also teach them to connect their lessons to a drum part of their own creation. It will also teach skills on how to play "on the spot" if they should ever be in a situation where they need to make up a drum part right then and there.
There's a strong likelihood that your student has one or more drummers they enjoy listening to, and would love to emulate. If not, suggest some to check out. Next, try to find out what specifically your student loves about their playing. Try to break down what the drummer is doing, and turn it into a lesson for your student. Just like an aspiring baseball player can learn a lot from emulating their favorite player's swing, your student can learn a lot from trying to emulate drummers they look up to. Not only is it fun for them, but it also teaches them how to work hard to attain a certain goal, such as a particular drum fill they like from their favorite drummer.
Learning an instrument can be discouraging. It can take years to get good. That's why your student needs encouragement to keep playing. Don't scold them if they haven't mastered what they were supposed to for the lesson. Encourage them. Tell them how good they could be with more practice and with more effect. Don't turn drum lessons into a punishment, or make it seem like they'll get in trouble if they didn't learn what they were supposed to. Instead, instill in them that they will face challenges on the road to becoming a good drummer, but that practice and a consistent effort can make success possible.