What’s your go-to filler activity when a lesson wraps up too early? I try to plan down to the minute, but sometimes something just clicks faster than expected and suddenly I’ve got 10 minutes to fill and 30 restless students staring at me. I’ve used everything from silent reading to “draw your learning” prompts to brain break trivia, but I’m always on the hunt for new ideas that don’t feel like busywork. The goal is to keep it low-prep, high-engagement, and not let the room dissolve into social hour chaos.

Honestly, sometimes I just let them talk. Not everything needs to be a structured activity. These kids get so few moments to just exist.

We never have a problem filling the time. There's always some discussion to be had about what we've been reading or writing. Sometimes the most interesting observations from students come in that unstructured time, so it's something I don't mind at all.

First: Brain Quest question cards, grade-level or previous grade, subject matter {me - science} or general subject with old-style Starburst, individually wrapped, I can toss to the correct answer as reward. Only those that raise hand, pay no attention to shout outs. Can only trade for different flavor at the passing bell.
Second: Have super spongy small US World Cup soccer ball. Toss underhand to student {one you know has answer}
Ask question from day’s lesson; they toss to another student and ask question of them {second student can consult with table mates} and so on.
This does require lots of prep in opening weeks of semester. Reward more Starbursts [individual wrapped, no nuts, little sugar high]
I buy Starbursts by the case each semester, tropical flavor are best.

Silent Ball: Have something soft to toss. Everyone who wants to play stands. You must throw and catch the ball in silence. If you drop the ball you must sit down until the next round. If you make noise, you are out. I add these rules to start: Must throw under hand and the ball/object must arc on its way to its intended target. The ball cannot hit anything in the room. Overhand throws or drilling it at someone means you're out. If your throw is bad/uncatchable, you are out. Play until only one person remains standing.
Silly rules to add to speed up the game:
Hot Potato - you must throw within one second of catching
Captain Hook - throw and catch with only one hand
Weak hand - same as above, but with your weaker hand
Pirate - stand on one leg
Tea parties - you cannot throw it back to the person who threw it to you.
Cyclops - must play with one eye closed.
I've played this with elementary, middle and high school students. Everyone loves it.

I teach English - and there are years that I have a separate, "fun" book that I read aloud to the class whenever we have extra time. No assignments, no discussions unless they initiate, just the enjoyment of listening to a story being read to them.

Give out exit tickets after the lessons. Students can draw or write their responses. You can also play guess the food/ movies games online. You can play games on the smart board. Students can help clean up the room as that's is always pencils on the floor.

I used to play the silent game (seniors). It’s not academic, rather self control or discipline. (It’s almost necessary to have a tile floor - easier done with carpet, but still difficult. I would offer the entire class with an A for the semester (a huge carrot) if they succeeded. Although unfortunately, better to start at the beginning of class which doesn’t deal with your question) But the kids loved it and it was kinda fun. My rule is if they make any noise they lose - that includes chair creaks, rustling, breathing, ANY noise. It’s possible, but very difficult. It’s usually over within 2 minutes, but they always want to try again. No class has ever gone more than 10 minutes! (I was a little worried, but I could always make them laugh)
But 10 minutes? I agree with Minnesota - free time - won’t kill you and certainly not the kids.

Madlibs it helps teach what parts of speech are and expand vocabulary and kids find them hillarious.

Google activities that build executive function.

Fun vocab games as exit tickets.

I always play Two Truths and a Lie. I feel like it creates a fun connection between the students and I. It's exciting to find out "personal" stuff about your teacher, like she surfs or has climbed Everest or doesn't know how to drive...

Blooket, Gimkit, or Kahoot.

1. For my classes, students are told to complete missing work if for some reason they finish early. Most students have something to do and the few that don't can usually find something productive to do. If they do not know know what to work on, I can tell them. Otherwise, they are to "fake me out" as if they are working on something for the class, so I don't have to assign more work (I never have to). They may also work on other classes' work at that point too (which usually is not that much time). They may also add more depth to the work they were assigned. Students usually do well with it because they like to think they can "con" the teacher into avoiding new additional requirements.
2. I purposely tell them to skip a certain part of their assignment for the day (that I knew I wasn't going to do anyway for time or whatever reason) , but I tell them it will be assigned if everyone gets finished early with the requirements (the "fake me out" notation in number one applies again here). Students generally love to skip things and not revisit it. They think they "won".
3. In general, I try to watch the time and pace (or stretch) things out if needed, so they can be productive for the period. I can add to requirement or take away requirements with the time. For example, instead of ten of something, they do three and vice-versa. I might have them think of a real life example of something too (write it down).
4. You can have them do a reflection sheet. I call it a BR/ET page (Bell ringer/Exit ticket). They have a page for two weeks (double sided): it has a bell ringer line on the top of a specific day's part and a reflection line on the bottom of that day. You could expand a reflection line requirement from one line to a paragraph, etc. as needed. You could also have them create something based on the lesson or have them write about a real life example of the lesson material. Bell Ringers and Exit Tickets are required at my school.
5. You might find a "go to" online thing that students can complete over an extended period of time. You can go to it whenever you have a weird schedule in a week or finish something else in bad time of the week (for example, to not start something new on a Friday). I use EverFi modules. Students have to complete Lesson 4 by the end of the year and I tell them they cannot advance past a certain point at a certain time. Sometimes students are absent and need to "catch up" to where they need to be.