TI favorite Scientific

Back in high school, this model has been recommended by the math teacher.
More uninteresting than trade price on amazon so I ordered it.
In my time as IT 83 was praised by the teachers for students doing S, so it's no great surprise to see that after 15 it is always the case!
Easily programmable, with internet (cable supplied) so no complaints on that side, it will accompany your carefree schoolboy.