Developing a class plotting scheduler but it has many logical errors, Can you help me

[superjohnellee]

function create_time_range($start, $end, $interval='30 mins', $format='12'){
	$startTime=strtotime($start);
	$endTime=strtotime($end);
	$returnTimeFormat=($format=='24')?'g:i':'G:i';

	$current=time();
	$addTime=strtotime('+'.$interval,$current);
	$diff=$addTime-$current;

	$times=array();
	while ($startTime<$endTime) {
		$times[]=date($returnTimeFormat,$startTime);
		$startTime+=$diff;
	}
	$times[]=date($returnTimeFormat,$startTime);
	return $times;
}

<div class="table-responsive">
                <form method="POST">
	                <table class="table table-bordered table-hoverable table-striped" id="tblClassScheduler">
	                    <thead>
	                       <tr>
	                         <?php
	                          $days=array("Monday"=>1,"Tuesday"=>2,"Wednesday"=>3,"Thursday"=>4,"Friday"=>5,"Saturday"=>6,"Sunday"=>7);
	                          for ($i=0;$i<COUNT($days);$i++) { 
	                            echo "<th>".date("D m/d",strtotime(" +".$i." days"))."</th>";
	                          }
	                       ?>
	                       </tr>
	                    </thead>
	                    <tbody>
	                    	<?php
	                    		$class_time=create_time_range('08:00','22:00','30 mins');
	                    		$j=0;
	                    		foreach ($class_time as $value) {
	                    			$j++;
	                    			echo "<tr>
	                    				<td>".$value."<br><input type='checkbox' name='class_time_mon".$j."' value='".$value."'></td>
	                    				<td>".$value."<br><input type='checkbox' name='class_time_tues".$j."' value='".$value."'></td>
	                    				<td>".$value."<br><input type='checkbox' name='class_time_wed".$j."' value='".$value."'></td>
	                    				<td>".$value."<br><input type='checkbox' name='class_time_thurs".$j."' value='".$value."'></td>
	                    				<td>".$value."<br><input type='checkbox' name='class_time_fri".$j."' value='".$value."'></td>
	                    				<td>".$value."<br><input type='checkbox' name='class_time_sat".$j."' value='".$value."'></td>
	                    				<td>".$value."<br><input type='checkbox' name='class_time_sun".$j."' value='".$value."'></td>
	                    			</tr>";
	                    		}
	                    	?>
	                    </tbody>
	                    <button type="submit" class="btn btn-primary" id="save_class_schedule" name="save_class_schedule">Save</button>
	                </table>
                </form>
            </div>