SHIRT POCKET:
3x5 memory cards*:
- blank
- calendar
- assignment card
pen, pencil
plastic cards:
- license
- health insurance
- debit
money
bus pass
business cards
Fundial (download yours)

JACKET:
cell phone,* headset
sunglasses
crystal ball (to see future)
keys with CPR mask attached
quarters
pencils
clock*

BACKPACK: I like lots of pockets so everything has its place.
Food & drink:*
- bagel & cheese
- muffin
- fresh fruit
- nutrition bar
- salad & dressing
- fork
- entreé
- water, one or two quarts

First Aid:*
- alcohol swabs
- bandaids
- vinyl gloves
- cough drops, herbal

Personal:
- comb
- nail clipper
- tooth care
- mirror
- mints
- vitamins
- tissues

Office:
- legal size folder, with
-- blank paper
-- notebook paper
-- sub summary forms
-- business cards
-- payroll sheets
-- quick study guides
- school folder
- calculator(s)
- glue stick
- white out
- pencils
- rubber bands
- postit notes
- paper clips, large

Misc:
- bus schedules
- bus tickets
- words to read on bus
- radio & headset
- microscope 30x
- magnifying glasses
- safety pins, assorted
- eyeglass repair kit
- rubber gloves & plastic bags*
- talking koosh*

Bike: (Your milage may vary)
- helmet
- gloves
- bike lights
- rain gear
- seat cover
- paper towel (for oily parts)

*Notes on above:
3x5 memory cards (color-coded helps):
If you have a perfect memory, you can save carrying these three extra cards. If you're like me, you might forget important information, potentially costing time, money, and credence. I'd rather do as Charley in Flowers for Algernon and write myself notes. "Go to skol."

Blank card, to take notes on throughout the day. If asked to cover another class, I write period, room number, key location, etc. Also, anything that has to be done before I leave the building, people to contact, follow up actions, reordering of room, returning borrowed equipment, etc. When it's all crossed off I leave.
When starting out, it doesn't hurt to add things like "return keys and folder" to the list. It'll become routine, but at the end of a day our mental circuits may not be at peak performance. It's not fun to get home and find a school key in a pocket.
On the card's other side, I write things to do after school, things to get on the way home, or do when I get home. This frees my mind to deal with immediate issues.

Calendar of assignments. When a teacher asks if I'm available on a certain day, I can quickly check, and note if they are going to request me. Often, this is between classes when time is short.

Assignment card. Teacher's name, school, arrival and departure times, subject, assignment number, phone number(s), parking space number, and so on.
I'm carfree and bus and/or bike to school, so I often write a note on a postit stating, "So-and-so's sub doesn't need parking space number xx on Day-of-week, month/day." I sign it, and give it to the secretary as I sign in. If you do this, don't write "today" as the note could still be there the next day.
Also, write the school's emergency number if classroom has a phone. This might be security, campus monitor, VP's office, or main office. You won't have time to look it up if you need it.

Cell phone. You don't have one? Get one. This is a valuable tool, not just a personal convenience. A minimal service plan will suffice. In a rare emergency it could save a life. If the classroom phone or intercom isn't working or doesn't exist, you can call the school office for help. It may even gain you assignments, depending on how your district does it. One job could pay three months' phone bill.

Clock. I like a cheap digital sports timer which includes a stop watch, though a wristwatch or cell phone is fine. I synchronize it with the school's clock. Timing presentations and seizures is easier with a stop watch. I can place it next to the seating chart and tell time without letting on.

Food and Drink. School food may be palatable where you work and the water in the fountains may be potable, but over the past 20 years this has become rare in public schools. I recommend taking your own food if you eat during the school day.
If you can afford water out of the vending machine, or there are water dispensers, or the fountains have filters, your bag will be lighter. A water bottle is still handy for staying hydrated. I refill mine to drink in the classroom, as there often isn't time to go to both a fountain/dispenser and the restroom between classes.

First Aid. Keep it simple -- we're not nurses. Standard proceedure is to send any student who is bleeding to the school nurse, if there is one. As a practical matter, an alcohol swab and bandaid are often all that's needed. Packaged alcohol swabs are cheap by the 100. Hopefully you've taken first aid and CPR classes, and know protocol for blood-borne pathenogens. "If it's wet and it's not yours don't touch it."

Rubber gloves & plastic bags. Waiting for the bus is a waste of time, so sometimes I pick up litter. It goes in the plastic bag if there's no trash can, and then into the bus waste basket. A second bag provides a place to put the rubber gloves, which may not be clean after use. Save the vinyl gloves for wet emergencies.

Talking koosh. A koosh ball works great, but any soft and easily caught object will do. Whoever has the talking koosh has the floor and no one else is supposed to talk. They decide who the next person is by tossing it to them.