O, T, T, F, F, S, S… Sequence Puzzle
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My students have really been enjoying the sequence puzzles I have been posting lately, so I thought I would challenge them with the O, T, T, F, F, S, S, … sequence.

This sequence puzzle asks: What is the next letter in the sequence?
Like I did with the M Heart 8 Sequence, I put each individual letter on its own magnet (using ceramic disc magnets) so I can add a new term to the sequence each day.
I find that putting the puzzle up piece by piece really raises the engagement level with my students. The first thing students do when they walk in the room is check to see what I added to see if their theory is correct.
Have you figured it out yet?
I ended up typing up 12 letters in total, but I doubt I will use them all with my students.
Still stuck? I will give you a hint. This is still a numerical sequence. I could just as easily ask, what is the next number in the sequence.
Free Download of O, T, T, F, F, S, S, … Puzzle
Click here to DownloadO, T, T, F, F, S, S Sequence (PDF)
2478 downloads – 23.25 KB
Puzzle Solutions
Puzzle solutions are available on a password-protected solution page. I do not openly post the puzzle answer keys because one of my goals as a resource creator is to craft learning experiences for students that are non-google-able. I want teachers to be able to use these puzzles in their classrooms without the solutions being found easily on the Internet.
Please email me at sarah@mathequalslove.net for the password to the answer key database featuring all of my printable puzzles and math worksheets. I frequently have students emailing me for the answer key, so please specify in your email what school you teach at and what subjects you teach. If you do not provide these details, I will not be able to send you the password.
Not a teacher? Go ahead and send me an email as well. Just let me know what you are using the puzzles for. I am continually in awe of how many people are using these puzzles with scouting groups, with senior adults battling dementia, or as fun activities in their workplace. Just give me enough details so I know you are not a student looking for answers to the puzzle that was assigned as their homework!
How many letters did it take before a student figured out the sequence?
It varied from class to class. Some figured it out right away. Others never did!
Beautiful. Just beautiful.