Use 

This drawing aid is primarily designed for physics lessons, since it allows you to draw an equalization curve through your points of data very easily. In addition, it features different circuit symbol stencils. There also is a plain version if you only want the functions. 

The template is metric.

Functions you can draw with this

• quadratic functions
• square root functions
• exponential functions
• (co)sine functions
• hyperbolic functions 

Circuit Symbols you can draw with this

• amperemeter
• voltmeter
• incandescent light bulb
• diode
• arrow
• cell
• power source
• plate Capacitor
• coil
• resistor
• connection