8 room, 160 student, 20 staff, school network.

You have a rather substantial and growing network here with a wide range of needs. I don't mean to say this at all to sound harsh or cruel but the honest truth is you need to have an IT professional here to manage this, and yes, it's going to cost A LOT to get it done properly. Sure, you can get by cheaply, but I guarantee if you skimp it will all come crashing down. I'm saying this because truly your best solution is going to be finding a network administrator who is willing to help set up and manage your network. Even if you don't need someone full time, either find someone part time or contract with a local IT professional who can do the job right. Knowledge of home wireless networking is little good in a school environment where you need to control user access, security, manage multiple networks, and domain environments.

That being said, this would be a big project even for me, as most of our customers are no more than 20 or 30 employees and computers. At minimum you need to have in place a nice firewall to manage network access, monitor traffic, and block intrusion attempts or attacks. You can also find routers that will do most of this, brands and features really come down to your preference and budget. Switches need to be manageable to support multiple VLANs that are needed for this network. Staff computers, resources, and data should not be accessible on computers where students may have access. Doing this requires separating your networks. Enterprise wireless access points are also recommended above just cheap wireless routers used as access points. Not only are true access points capable of handling more concurrent connections properly, but the are often able to handle multiple SSIDs and VLANs which isn't something cheap home wireless routers can do. One AP can do the work of four wireless routers meaning less cost, less failures, and less complexity.

You are also going to need servers, if you don't already, for managing storage, software, and user account access. You COULD get away with using a single or possibly two servers to do this, but I wouldn't recommend that. Invest in high availability. No one, not your students nor your staff, want your network to go down for days due to a glitch with your server. A simple high-availability cluster can be built with two "nodes" which are your computational servers plus one shared storage, called a SAN. This can even be a third server setup for ISCSI, but usually is a specialized SAN device built for better reliability, performance, and expansion.

I know this maybe a little late, but the number of APs, size of your Internet connection, what device is serving as your DHCP server and the sq ft of your school would be a great help in helping you. As choucove mentioned, you have moving in to a much more expensive place, but you don't need a full time IT person, just the part time help of someone/some company that provided business class IT help.

I have used/tested Meraki, but I prefer Ruckus wireless. I bet you could use less AP, one 24 port PoE Switch (Zyxel GS-1910-24P highly recommended) with a single local ZoneDirector for a lot less, and if you don't purchase maintenance in years 2 and 3, your network will still operate.

Key differences:
1) Most of Ruckus's APs handle 250 - 512 active connections, Meraki ~40-50
2) If you don't buy maintenance from Meraki, your APs just stop working.
3) Cloud manager for Meraki, your choice from Ruckus, local appliance or cloud on VMware

(Full Disclosure) I am a full time RF Engineer, Ruckus WiSE certified, have and like my demo MR18 AP from Meraki and am Blue Socket certified as well as 30+ years in networking.

BTW ... Schools get a special discount from most AP vendors ...

P.S. If you need help or more advice, contact me at pa da pa -at- g mail dot com (assembling the email address is your first test).