Category Archives: technology

#MTBoSBlaugust 4 Calculator “Museum”


I got distracted while in my classroom yesterday looking at my old calculators from college days.  I thought about them when Sara VenDerWerfshared shared about her calculator museum.

Ever so often I tell my students about my “good ol’ days.” I show them my

  • high school (and college) slide rule – IT WORKS

!Slide Rule

  • TI SR 10 (Slide Rule) w/charger but no longer chargeable – receipt for $36.88  (only used for during college chemistry 2nd semester)

SR 10 Box      TI SR10

  • TI-30 LED (9-volt battery) – IT WORKS! initial price of $19.88 (a 1 hour special late evening!) bought 2 years later – maybe used for 1 or 2  college classes (can’t remember for certain)

TI 30 box (2) TI 30



  • I also show them a 1937 book of tables for square roots, logs, and trig given by a parent of one of my former students – it’s really just an older low tech calculator.  IT WORKS!  (If there’s class time, I tell the story of Napier solving the chicken thief mystery – although there are doubts over the authenticity of that story)


And now I pass on my love for Desmos – so much so that a student wrote my name in tiny Desmos words (maybe about 50-100 “Desmos” per letter of my name) on my whiteboard during an informal lunch study hall.  I wish I had a picture of that!  This will have to do:


That student moved away before i got to hint at gifting me a pair of desmos socks!!!




I use Desmos graphing calculator but much more often the TI calculator.  I am trying to learn more this summer and was wondering how to graph “holes” in rational functions.  Between a resource found with Google and the user manual, I know have learned how to graph a hole.



Edit the display of the point where the hole in the function occurs.




Now I can refer back to this post in case I forget 🙂

Alternate online graphing calulators