LED control question

Using Arduino LEDs and Multiplexing
1

These LEDs

DC Forward Voltage (VF): Red: 2.0-2.5Vdc, Green: 3.2-3.6Vdc, Blue: 3.2-3.6Vdc, DC Forward Current (IF): Red: 400MA/ Green: 350MA/ Blue: 350MA
Luminous Intensity: Red: 45-50LM, Green: 65-75LM, Blue: 20-25LM Wave Length: Red: 620-625nm, Green: 520-530nm, Blue: 460-465nm

If the current is limited to under the rated current, say 1/3 to 1/2,

can a resistor & N-channel MOSFET be used to drive them on/off?

2

Sure, but consider the power dissipation of the resistor for your 3W LED. Might want to consider this MOSFET circuit..

Transistor - MOSFET Constant Current Driver