The default beaming is set via the time signature.

The beaming breaks at the beats - to show the beats.

1) In the Time Signature Tool you can define 9/8 as 9 beats, each beat with a duration of an eighth.

This definition will beam each beat (= each eighth) by itself.

2) You can also define 9/8 as 3 beats, each beat with a duration of a dotted quarter.

This definition will beam each beat (= each dotted quarter) by itself so that the eighths are beamed in groups of 3.

If you use the context menu to change the time signature to 9/8, then you will get the default definition of 2) = eighths beamed in groups of 3.

Changing the time signature may or may not change the beaming of notes already entered.

If you want to change the beaming of notes already entered, then “Rebar Music” is your friend.

You have “Rebar Music” in the dialog box Time Signature, and also in the Utilities menu.

Thanks, Peter.

I can't believe I forgot this. 

Cheers

I need help!!!!  My groupings of 8th and 16th notes will not beam together

Post a picture of what you want to happen.

...And a picture of what is going wrong would be helpful too.