Informal Informative Writing
Hand out 3 x 5 cards, or slips of scratch paper as students enter the classroom. Ask students to write, anonymously, one or two sentences indicating the particular kind(s) of problem(s) they experienced while doing the recent homework assignment. Collect, then quickly read these slips, either silently (for your information) or aloud (so students can see that others may have had difficulty with same issues.)
This strategy gives the students time to focus on the precise assignment and provides the teacher with an idea of what the students do/do not understand. You, the teacher can then proceed, review or re-teach according to the needs revealed on the admit slips.
If you have access to a digital app, like Padlet, you can have students write their response and post it on the “board”. Set Padlet for write only until all students have posted. Preview, then switch to read so students can see what classmates have written. You can decide whether or not these posting should include student name or be anonymous.
When presenting lots of new information, stop periodically and ask students to write summary sentences. At strategic points in the presentation, pause a moment and have the students focus and reflect on what they have been hearing. They should write in their own words (1) a definition of the concept, or (2) a summary of what they have learned so far. Allow a couple extra minutes for a few students to read aloud what they’ve written. These readings will reinforce the value of the writing while revealing whether or not the students are grasping the ideas being presented. Frequently, the student will phrase the definition in words more familiar to their classmates and more easily comprehensible than those in the formal definition or words you may have been using.
This activity is an opportunity for students to pause and digest, and for you, the teacher, to conduct a spot or formative assessment of what is or is not being understood.
Exit Slips 
Five minutes before the end of the period, distribute 3 x 5 cards or slips of scratch paper to each student. Ask students to write in their own words what has been taught that period and what they have learned. Again, content not form is important in these notes. Merely collect these anonymous notes as the students leave the classroom. Reading them later will give you a better understanding of what the students have grasped and which of them need further clarification before proceeding on to new material or concepts. A digital app like Padlet can work here, too.
These “writing to learn” activities are effective ways for both student and teacher to learn, in a non-threatening way, whether or not the information taught has been learned. If the students can find the words to write fairly clearly what was taught in the lesson of the day, they know that they know; if they can’t, they know that, too, and can either ask for help or study themselves. They don’t have to wait until a graded assignment to learn what they know. These admit, summary and exit slips help tell who knows what, now.
 Geere, Anne Ruggles. (1985) Roots in the Sawdust – Writing the Learn Across the Disciplines. Urbana, Illinois.