Thanks kooogy, i've modified my code and its now calculating the score.

However, the scorequick doesn't seem to increase. The value of 497.5 is correct and scorestandard works so the limits are correct. Have you any suggestions?

 

Block standardBlock;             // Block object for standard scoring block
Block quickBlock;                   // Block object for quicker scoring block
Block catcherBlock;               // Block for the catcher
float count = 0;                        // Counter for standard blocks that have fallen
float count2 = 1;                     // Counter for quicker blocks that have fallen (initialised at 1)
int scorestandard;                // Score for standard blocks
int scorequick;                      // Score for quicker blocks
int scoretotal;                        // Variable for total points score
float yposBlock1;                  // Variable to store y position of a standard falling block
float xposBlock1;                  // Variable to store x position of a standard falling block
float yposBlock2;                  // Variable to store y position of a quick falling block
float xposBlock2;                  // Variable to store x position of a quick falling block

 

void setup() {
  size(900,500);
  standardBlock = new Block(color (0), random (10,890), 0, 5);               // Initialises standard block object
  quickBlock = new Block(color (150), random (10, 890), -20, 7.5);        // Initialises quick block object
  catcherBlock = new Block (color (0), mouseX, 500, 0);                          // Initialises catcher block object
}

void draw() {
  background(255);
  float xuplimit = (mouseX + 20);                                                            // Variable to calculate the right hand edge of catcher block
  float xlowlimit = (mouseX - 20);                                                           // Variable to calculate the left hand edge of catcher block
  if ((yposBlock1 == 500) && (xposBlock1 <= xuplimit) && (xposBlock1 >= xlowlimit)) {        // Increments standard score   
       scorestandard ++; }                                                                   
  if ((yposBlock2 == 497.5) && (xposBlock2 <= xuplimit) && (xposBlock2 >= xlowlimit)) {      // Increments quick score          

      scorequick ++; }                                                                       

if (count <= 10) {                                                                           // Determines how long the game lasts by how many blocks will fall
     standardBlock.move();                                                                   // Operates the standard block
     standardBlock.display();                                                                // Displays the standard block
     quickBlock.move2();                                                                     // Operates the quick block
     quickBlock.display();                                                                   // Displays the quick block
     catcherBlock.move3();                                                                   // Operates the catcher block
     catcherBlock.display2(); }                                                              // Displays the catcher block
     else {                                                                                                    // What to do when game ends
       scorequick = (scorequick * 5);                                  // Increases points score of quicker block by 5 as they are harder to catch
       scoretotal = (scorestandard + scorequick);                                            // Calculates the total score
       println ("You scored " + scoretotal);                                                 // Tells the player how many they scored
       exit (); }

}

class Block {                       // Defines Block class
  color c;                       
  float xpos;
  float ypos;
  float yspeed;
 
 Block(color tempC, float tempXpos, float tempYpos, float tempYspeed) {                    // Initialises the blocks variables        
    c = tempC;
    xpos= tempXpos; 
    ypos= tempYpos;
    yspeed=tempYspeed;
  }
 
 void display() {               // Method to display the standard and quick blocks
    rectMode(CENTER);
    fill(c);
    rect(xpos,ypos,10,10);
  }
 
 void move() {                     // Method to operate the standard block
    ypos = ypos + yspeed;
    yposBlock1 = ypos;
    if (ypos > height) {
      ypos = 0;
      xpos = random(10,890);
      count ++;
      xposBlock1 = xpos; }
  }
 
 void move2() {                   // Method to operate the quick block
    if (count / count2 == 10) {   // Only operate when 10 standard blocks have fallen
    yposBlock2 = ypos; 
    ypos = ypos + yspeed; }
    if (ypos > height) {
      ypos = -20;
      xpos = random(10,890);
      count2 ++;
      xposBlock2 = xpos; }
  }
 
 void display2 () {              // Method to display the catcher block
   rectMode(CENTER);
   fill(c);
   rect(xpos,ypos,40,10);
 }
 
 void move3 () {                // Method to operate the catcher block
   ypos = 500;
   xpos = mouseX;
 }
}