Scaffolding is widely considered to be an essential element of effective teaching, and all teachers—to a greater or lesser extent—almost certainly use various forms of instructional scaffolding in their teaching. In addition, scaffolding is often used to bridge learning gaps—i.e., the difference between what students have learned and what they are expected to know and be able to do at a certain point in their education. For example, if students are not at the reading level required to understand a text being taught in a course, the teacher might use instructional scaffolding to incrementally improve their reading ability until they can read the required text independently and without assistance. One of the main goals of scaffolding is to reduce the negative emotions and self-perceptions that students may experience when they get frustrated, intimidated, or discouraged when attempting a difficult task without the assistance, direction, or understanding they need to complete it."
(Image from https://en.wikipedia.org/wiki/Instructional_scaffolding )

(video source on module https://www.youtube.com/watch?v=CTR_snb-0nQ&feature=youtu.be)

One technique of assessment I often use is  to have one student try to teach-present to another student or the class what they have learned. Sometimes I use this combined with an analogy the student can present or a concrete example.