I use my own PBIS system in the classroom, where my students earn raffle tickets for following directions, getting correct answers in class, and working hard on their independent and/or partner practice. This has encouraged class participation. Since students get many extra tickets for correct answers on independent and partner practice, students are also encouraged to master the material. At the end of each class period, I draw 1-4 names for a small prize.
I also frequently give positive phone calls home to students who have earned them in class, whether it be about behavior or academics.
For example, as seen in the text chains with three random parents above, I give both positive and negative updates as to what students are doing in class. These are often tied to academics, such as one student getting his work done early and assisting other students with their problems.
Additionally, I often tie incentives to academic achievement. For example, I had a pizza party for all students who did their homework daily for the first month of school, and I will have an ice cream social for everyone who gets a 100% on their weekly integer operations quick quiz by Thanksgiving. This gives extra motivation to students who need it and otherwise validates students who do not.
I give positive school Liveschool points primarily for academic accomplishments, such as asking content questions or being engaged in class discussion. This also provides extra motivation to students to perform well academically. While I give some points for behavior, most points are earned through academics. Students can use these points at the school store during lunch.