Teaching students with creativity and powerful ideas does the only thing that really motivates students to learn: it piques their curiosity, and makes them want to learn whatever you're teaching. It also all but eliminates behavioral issues and absenteeism, because students won't want to miss a day.
One way I found to ensure that students were motivated every single day was to do what used to be called an "anticipatory set" that hooked my students before I even began to teach the skill or concept.
What is that? It's an activity, a film clip, a sound bite, a "burning question" or a startling statement that makes them sit up and take notice. Sometimes I used questions designed to rile them up and make them want to argue with me. Sometimes I did things that confused them, or had them do a task that made them wonder what on earth I was up to.
Most of all, that anticipatory set and the activities that follow must be rooted in or help them deal with the "real world" they inhabit in some way. Even if I was teaching Shakespeare or something as far from their daily lives as Beowulf, I tied the lesson to something they knew or needed to know.
Making students think about Grendel and Beowulf as a video game or comic book, and having them create both, made them want to read the saga. Having them "translate" Shakespeare into "streat" language was also a really fun process. I had kids in two circles, one seated, one standing. Each seated student read a passage of Shakespeare as written and the student standing behind him or her had to "translate" the passage into the kind of language they would use, say, talking to a friend in the cafeteria.
I still get Facebook messages from students I taught decades ago who remember some of my lessons very vividly, and have used them to motivate their own children. That always makes me feel wonderful!