My students have been driving me CRAZY writing run on sentences lately, including comma splices. It's the biggest error in their writing! I searched online and came up with 4 "warm ups" and a quick assessment to help teach them to STOP USING RUN ON SENTENCES! This includes 4 warms ups, 2 which include QR codes for the students to scan that will take them to an article that they can read/listen to about run ons and to an outside "quiz" that is pretty good. There is also a reference to "BrainPop," if your kids have that app. :-) Then there is a quiz. You can also use elements of this even if your students don't have iPads! It can be used with a whole class or as literacy centers.