Hi Donna ~
Most of the queues at Disney are now mainstreamed to accommodate Guests traveling in wheelchairs or EVCs. Queues that require Guests in wheelchairs to enter through alternate queues should see a Cast Member (CM) for assistance. They'll give you a return time to come back to the attraction based on the current wait time. There aren't many of these and most are found at Magic Kingdom or Star Tours at Hollywood Studios.
Guests who are unable to wait in a regular queue can request a Disability Access Service Card (DAS) by going to Guest Relations at a theme park. CMs ask them some questions so they can best accommodate their specific needs. They'll take their photo for the DAS, go over the terms and conditions and have them (or a parent) sign the card. For a party over 6, you may need to speak with a manager.
Once a Guest obtains a DAS, they can go to an attraction and see a CM at the entrance to get a return time to enter the FastPass+ (FP+) or other alternate entrance if necessary. The CM will fill in the information on the DAS indicating the return time which is determined by taking the current wait time and subtracting 10 minutes. The Guest with the DAS will not need to be present to get a return time for attractions but must be present when entering the queue and boarding the attraction. Once the return time on the DAS is reached, the Guest with the DAS and their party can go to the attraction anytime afterwards - there is no pressure to make it back within a certain time frame.
Guests can only obtain a return time for one attraction at a time but can get another DAS return time as soon as they've finish one. If available, FP+ can be used in addition to the DAS.
Here is a list of
Frequently Asked Questions about the DAS.
Wishing you minnie magical memories :-) Allison V.