I taught one of [Mr. Radosevic’s] classes about conic sections using string models that I made over 40 years ago and a 35mm slide projector. The support base of the right circular cone is giant plastic tinker toys, and the center support is an old wooden broom stick. - John McEniry '68

On April 25, 2018, Mr. John McEniry returned to Rockhurst. This technology teacher enlightened Algebra II students with some *old school* technology to help them understand conic sections. Below are some student reflections from the event.

Mr. McEniry’s presentation was extremely interesting. It was interesting how he showed us the hyperbolic parabolas. He used his slide show to project light onto his diagram to show the different hyperbolic parabolas. One of the coolest cross sections that he showed was the circle of light, which was changed shapes when it was projected onto the diagram, making the light look like a Pringle. - Patrick Mullen

Mr. McEniry’s talk was very interesting to me because he was able to show how hyperbolic parabolas worked in person instead of on a screen. Because I got to see how the parabolas formed it was easy to understand. It was cool that he made the slides and the model himself because it showed how interested he was with his project. - Joe Patton

My favorite part of the light show was when he made a Pringle. The fact that he made all of these things by hand blew my mind. I also enjoyed the leprechaun trick. That was neat. - Owen Franklin

Mr. McEnry’s Hyperbolic Paraboloid Presentation was an interesting and educative experience for my Algebra 2/Trigonometry class. The presentation consisted of an elaborate cardboard and twine model of a hyperbolic paraboloid, while later on we were shown pictures of how it is seen today. The cardboard model, with light being casted on it, illustrated in three dimensions the cross sections of hyperbolic paraboloids. Some of those cross sections were on the vertical axis a parabola, while on the horizontal axis hyperbolas would be the name of the cross sections. Overall, the presentation helped clarify parabolas in our mathematics class and was an enjoyable lecture for our class. - Ryan O’Connell

Mr. McEniry’s presentation about conic sections was pretty cool. At first I didn’t understand what he was going to do with the old projector and the string setup, but he did it pretty well. The way he used light with the string setup was pretty creative. - Matt Coble

Being a visual based learner in most circumstances it helped me to grasp the subject better. I also thought the leprechaun thing was cool because it was all based on how the picture was drawn. It was an interesting optical illusion. - Grant Geiger

I really enjoyed Mr. McEniry’s, the show was really interesting. I really learned more about parabola’s and the way they work. He told us about how they used to have parabola’s for airplane hangers and he also made the parabola look like a Pringle. We really use parabola’s for constructions and many other things we need them for today. - Yohannes Assefa

Mr. McEniry taught at Rockhurst for 37 years. He taught in the mathematics department, but was also responsible for starting the Rockhurst High School computer department. Despite being in retirement, he enjoys coming back to Rockhurst and share some of his favorite bits of wisdom with students. As can be read above, the students still appreciate his gifts.

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