<#
    .SYNOPSIS
        Designed for the use of the schools team for a new intake of students, parents etc.
        It can be used for one particular operation or all operations required
        for the new intake. It will also give you the statistics of time taken at the end.
    .DESCRIPTION
        Designed for the use of the schools team for a new intake of students, parents etc.
        It can be used for one particular operation or all operations required
        for the new intake. It will also give you the statistics of time taken at the end.
    .PARAMETER ALL
        Will run all options. (DEFAULT)
    .PARAMETER File
        Path to a CSV file containg the new students
    .PARAMETER DisabledUsers
        Removing Of Disabled Users
    .PARAMETER Spaces
        Removing Of Spaces In The SAMAccountName,UPN, Mail Attributes
    .PARAMETER StudentInfo
        Sets Student Target And Proxy Addresses
    .PARAMETER LocationInfo
        Sets City And Company Information For Users
    .EXAMPLE 
        ./New-Year.ps1 -Path 'C:\Powershell\CSV\SchoolsList.csv' -All
    .EXAMPLE
        ./New-Year.ps1 -Path 'C:\Powershell\CSV\SchoolsList.csv' -DisabledUsers
    .EXAMPLE
        ./New-Year.ps1 -Path 'C:\Powershell\CSV\SchoolsList.csv' -DisabledUsers -Spaces -StudentInfo
#>                   
[CmdletBinding(DefaultParameterSetName='ALL')]                 
param                         
(                        
    [Parameter(Mandatory=$true,ParameterSetName='All',HelpMessage ="Path to the CSV containing the list of Schools")]                        
    [Parameter(Mandatory=$true,ParameterSetName='Selective',HelpMessage ="Path to the CSV containing the list of Schools")]                      
    [ValidateScript({Test-Path -Path $_})]            
    [String]                        
    $File            
,                        
    [Parameter(Mandatory=$false,ParameterSetName='All')]                        
    [switch]                        
    $All                        
,                        
    [Parameter(ParameterSetName='Selective')]                        
    [switch]                        
    $DisabledUsers                        
,                        
    [Parameter(ParameterSetName='Selective')]                        
    [switch]                        
    $Spaces                        
,                        
    [Parameter(ParameterSetName='Selective')]                        
    [switch]                        
    $StudentInfo                        
,                        
    [Parameter(ParameterSetName='Selective')]                        
    [switch]                        
    $LocationInfo                        
)                        
Begin             
{            
    #Remove Disabled Users                        
    Function Remove-DisabledUsers                         
    {                        
        Param(                        
            [Parameter(Mandatory=$true)]                        
            [string[]]$SchoolList                        
        )                        
        $start = Get-date                        
                        
        Write-verbose "$(get-date -format g) Starting Removing Disabled Users.... "                        
                        
        Foreach ($School in $SchoolList)                        
        {                        
            $ou = 'OU=users,OU=' + $School + ',OU=foo1,DC=foo,DC=co,DC=uk'                        
            Get-QADUser -Title "student", "teacher","staff","parent" `
                -SearchRoot $ou `
                -SizeLimit 0 `
                -IncludeAllProperties |                        
                Where-Object {$_.useraccountcontrol -eq 514 -or $_.useraccountcontrol -eq 66050 }|                        
                Delete-ADUser                        
        }                        
                               
        Write-verbose "$(get-date -format g) Finished Removing Disabled Users.... "                        
        Write-verbose "User cleanup completed in $((New-TimeSpan -Start $start).TotalMinutes) Minutes"                        
    }                        
                            
    # Remove Spaces                        
    Function Remove-SpacesFromAccounts             
    {                        
        Param(                        
            [Parameter(Mandatory=$true)]                        
            [string[]]$SchoolList                        
        )                        
        $Start = Get-Date                        
        Write-Verbose "$(get-date -format g) Removing Spaces From Accounts.... "                        
                        
        Foreach ($School in $SchoolList)                        
        {                        
            $ou = 'OU=users,OU=' + $School + ',OU=foo1,DC=foo,DC=co,DC=uk'                        
            $Users = Get-QADUser -Title "student", "teacher","staff","parent" `
                -SearchRoot $OU `
                -SizeLimit 0 `
                -includeAllProperties |                        
                Where-Object {$_.UserPrincipalName -match "\s" -or $_.samAccountName -match "\s" -or $_.mail -match "\s"}                        
                                    
            Foreach ($User in $Users)                        
            {                        
                $Sam = $User.SamAccountName                        
                $Sam1 = $Sam -replace " ",""                        
                $NewSam = $Sam1 -replace "'",""                        
                        
                $UPN = $User.UserPrincipalName                        
                $UPN1 = $UPN -replace " ",""                        
                $NewUPN = $UPN1 -replace "'",""                        
                        
                $Mail = $User.Mail                        
                $Mail1 = $Mail -replace " ",""                        
                $NewMail = $Mail1 -replace "'",""                        
                        
                Set-QADUser -Identity $Sam -ObjectAttributes @{Mail = $NewMail}                        
                Set-QADUser -Identity $Sam -UserPrincipalName $NewUPN                        
                Set-QADUser -Identity $Sam -SamAccountName $NewSam                        
            }                        
        }                        
        Write-verbose "$(get-date -format g) Finished Removing spaces from accounts"                        
        Write-verbose "Space removal completed in $((New-TimeSpan -Start $start).TotalMinutes) Minutes"                        
    }                        
                            
    Function Set-StudentInfo             
    {                        
        Param(                        
            [Parameter(Mandatory=$true)]                        
            [string[]]$SchoolList                        
        )                        
        $start = Get-date                        
                                
        Write-Verbose "$(get-date -format g) Setting Student Proxy and Target Addresses.... "                        
        # Assign Target Address and Proxy Address to Students                        
                        
        Foreach ($School in $SchoolList)                        
        {                        
            $ou = 'OU=users,OU=' + $School + ',OU=foo1,DC=foo,DC=co,DC=uk'                        
                                    
            $users = Get-QADUser -Title "student" -SearchRoot $OU -SizeLimit 0                         
                                    
            Foreach ($user in $users)                        
            {                        
                $TargetAddress = 'smtp:{0}@foo1.co.uk' -f $user.samAccountName                        
                $ProxyAddress = 'SMTP:{0}@{1}.foo.co.uk' -f $user.samAccountName ,$School                        
                        
                Set-QADUser -Identity  $user.Name -PasswordNeverExpires $false                         
                Set-QADUser -Identity  $user.Name -ObjectAttributes @{TargetAddress=$TargetAddress}                        
                Set-QADUser -Identity  $user.Name -ObjectAttributes @{ProxyAddresses=$ProxyAddress}                        
            }                        
        }                        
                                
        Write-Verbose "$(get-date -format g) Setting Student Proxy and Target Addresses.... "                        
        Write-Verbose "completed Setting student info in $((New-TimeSpan -Start $start).TotalMinutes) Minutes"                        
                        
    }                        
                            
    Function Set-LocationInfo             
    {                        
        Param(                        
            [Parameter(Mandatory=$true)]                        
            [string[]]$SchoolList                        
        )                        
        $start = Get-date                        
                                
        Write-Verbose "$(get-date -format g) Setting City And Company Information...."                        
        # Write City And Company Information                        
                        
        Foreach ($School in $SchoolList)                        
        {                        
            $ou = 'OU=users,OU=' + $School + ',OU=foo1,DC=foo,DC=co,DC=uk'                        
                        
            Get-QADUser -SearchRoot $OU -sizeLimit 0 |                        
                Set-QADUser -Company $School -City "city1"                           
        }                        
                                
        Write-Verbose "$(get-date -format g) City And Company Information Successfully Written. " -ForegroundColor Yellow                        
        Write-Verbose "completed Setting city, and company info in $((New-TimeSpan -Start $start).TotalMinutes) Minutes"                        
    }                        
}                        
End                        
{                     
    $SchoolList = Import-Csv -Path $File                        
                               
    IF ($PSCMDLET.ParameterSetName -eq "All" -OR $DisabledUsers)                        
    {                        
        Remove-DisabledUsers -SchoolList $SchoolList                        
    }                        
    IF ($PSCMDLET.ParameterSetName -eq "All" -OR $Spaces)                        
    {                        
        Remove-SpacesFromAccounts -SchoolList $SchoolList                        
    }                        
    IF ($PSCMDLET.ParameterSetName -eq "All" -OR $StudentInfo)                        
    {                        
        Set-StudentInfo -SchoolList $SchoolList                        
    }                        
    IF ($PSCMDLET.ParameterSetName -eq "All" -OR $LocationInfo)                        
    {                        
        Set-LocationInfo -SchoolList $SchoolList                        
    }                        
}

That's what I get for not testing it first... sorry about that I forgot the CmdletBinding statement... I updated the code.

Anyways Shay is you're man when it comes to the AD Stuff.  I was more trying to highlight the work flow and some of the v2 features (comment based help, parameter binding, validation, etc...)

As an aside after going through this script... unless your domain is really massive (i don't think it is or your original script shouldn't have worked) your target should be -le 10 min.  If this script takes longer than 10 min you still have some more optimizations to do.

Hope that helps,
~Glenn

p.s. sorry to script and run, but my wife would like to leave on vacation....