pretty much all bargello's are easy- they are strips sewn together- cut into strips and arranged- pick up a bargello book like the one Woody recommended. there are a number of books out there. the key to a bargello is a design wall- so as you cut the pieced strips you can hang them side by side, moving them up & down to achieve the pattern you find pleasing. there are a number of bargello table runner patterns for smaller projects.
if you & your students can cut accurate strips & sew a 1/4" seam bargello's are beginner friendly patterns.