S (school bus) endorsement. You'll have to get the "P" (passenger) endorsement first, then undergo a background check.
Class C CDL with School Bus endorsement.
Class C CDL with School Bus endorsement.
Only if you have the appropriate passenger endorsement.
There is no "school bus CDL". You either have a Class C or Class B CDL with a school bus endorsement. A Class C, you can drive any bus under 26,001 lbs. GVWR. If you get a hazmat endorsement, you can transport hazardous materials in any vehicle 26,000 lbs. GVWR or less. If you have a Class B, technically, you can drive any single vehicle with a Gross Vehicle Weight Rating of more than 26,000 lbs, but you're not going to get hired to drive a Class 8 with an unsynchronized manual transmission without any experience.
Once you have the endorsement, you can keep it. As far as I know, there isn't a renewal on that endorsement.
Getting a regular passenger endorsement won't be a problem (the school bus endorsement, you won't be eligible for, however).
You need the passenger (P) and School Bus (S) endorsements.
No... to drive a bus unsupervised, you need an unrestricted, full-on CDL license, with a passenger endorsement. You may not legally operate a bus - loaded or empty - otherwise.
Your question doesn't make any sense. What is a "26,001 lbs. restriction", exactly? A Class B CDL covers commercial single vehicles with a GVW of 26,0001 lbs. and higher. You would need to get a school bus endorsement before driving a school bus, though.
You can drive a taxi or a 15 passenger van. When it comes to a bus designed to transport more than 15 passengers (including the driver), you can't even drive the bus empty - let alone transport passengers - on a learner's permit. You must have the passenger endorsement in order to drive the bus, and you don't get that endorsement until you take the road test in the appropriate class of passenger vehicle - hence, by the time you get the endorsement, you actually have a CDL.
Depends on the Gross Vehicle Weight Rating. If it's under 26,000 lbs., you'd need a Class C CDL with the "S" endorsement for school bus (a passenger endorsement plus background check). For the larger ones which gross over 26,000 lbs., you'd need a Class B CDL with "S" endorsement.
First, you take the written tests (General Knowledge, Air Brakes (if applicable), and Passenger). Then, you have to submit fingerprints and undergo a state background check (for the S endorsement, which is a passenger endorsement specifically pertaining to school buses). You'll then get a learner's permit. Once you're ready for your road test, you'll conduct a road test in a bus of the appropriate class, show that you can do an adequate pre trip inspection, and, if you pass, you get your CDL. If you do this before your background check comes back, you'll have to get a duplicate issued once it comes back, in order to have the "S" endorsement on your licence - you won't get it until you pass the background check.