Multiple LEDs, give each their own resistor?

Hi,

After getting the basic’s made on a bread board, I wanted to do a couple “toy” projects with/for my kids. mostly to help learn the soldering.

  1. a “lightsaber”, with a switch to change colors.
  2. a statue with a PIR senor, when active it changes the color of a few LEDs

A question i have for both, can I (or should I) split the wire then put a resistor before each LED or put a resistor then spilt the wire for each LED.

Does it mater how many LEDs I’m chaining together? for the lightsaber the first model will likely be short and then I’ll move up to a collapsible one.

ps.
Just getting into hardware/circuitry, I’ve been a programmer for awhile, but my last experience with circuitry was an intro class 20 years ago. so my knowledge is spotty to say the least. Also the statue is Electronic motion-detecting Watcher by svenny - Thingiverse i still need to figure out the usb charging ports but that is a different topic

Didn’t quite understand what you meant.
Which product suite are you currently using.
You can provide us with a picture or video of the problem, so that we can understand and analyze it, and then we can help you solve the problem.

I got the Arduino 3 in 1 kit, but my question is more of a general circuitry question then about the kit or Arduino.

since you asked for a picture I guess more simply put, which picture is set up better the one with the green LEDs or the one with the Blue and why? Also would it matter if there was more LEDs?

Thanks for your help

It is recommended that you connect resistors to each LED individually in the manner shown on the left, mainly to limit the current flow through the LEDs to protect them from damage and to ensure their proper operation.
LED is a current-driven device and its brightness and color are determined by the current.The electrical characteristics of LED are non-linear, which means that when the voltage varies within a certain range, the current of the LED will increase dramatically. If too much current is passed through the LED, it may be damaged by overheating.