The word Scale used alone always means Strength/Mass Scale in Fudge any other Scale, such as Speed, or Strength without Mass, will be defined as such.
Each level of Strength (from Terrible to Superb) is defined to be 1.5 times stronger than the previous level. A character with Good Strength is thus 1.5 times as strong as a character with Fair Strength. Note that this progression is not necessarily true for any other attribute.
There is a wider range of strength in humans than dexterity, for example: Superb Dexterity is only about twice as good as Fair Dexterity.
Strength Scale increases in the same way: a Scale 1, Fair Strength individual is 1.5 times stronger than a Scale 0, Fair Strength individual. This holds for each increase in Scale: a Scale 10 Superb Strength creature is 1.5 times stronger than a Scale 9 Superb Strength creature, for example.
At this point, it is tempting to say that a Scale 1 Fair Strength is equal to a Scale 0 Good Strength. This is true for Strength, but not for Mass. Scale really measures Mass, or Density, and Strength just goes along for the ride.
In Fudge, Mass has a specific meaning: how wounds affect a character. (This may or may not coincide with the scientific definition of Mass.) It takes more human-powered hits to weaken a giant than a human, for example.
She may not really be a healthy giant, but her sheer bulk means that human-sized sword strokes don’t do as much damage relative to her as they would to a human unless they hit a vital spot, of course. Likewise, a pixie can be healthy and robust, but not survive a single kick from a human. The difference is Mass, and the strength related to it.
A Scale 1 Fair Strength fighter has an advantage over a Scale 0 Good Strength fighter, even though their Strengths are equal. The Scale 1 fighter is less affected by the other’s damage due to his mass. Therefore, do not blithely equate Scale 0 Good with Scale 1 Fair.
Of course, the GM may envision a less massive but harder to kill race than humans. This is best handled by a Racial Bonus, either as a Toughness Gift (Tough Hide, or Density either one would subtract from damage), or by a bonus to Damage Capacity.
The GM may decide that increased Mass does not necessarily mean of greater size the race may be of denser material. Dwarves in northern European legend were derived from stone, and are hence denser than humans.
Such a dwarf hits harder and shrugs off damage easier than most humans: he is Scale 1, though shorter than a human. (Of course, the GM should define dwarves’ attributes and Scale to her own requirements.) Normally, Strength and Mass are handled by a single Scale figure. That is, if a creature is said to be Scale 7, that means Scale 7 Mass and Scale 7 Strength. Strength can vary within each race just as it can for humans.
You can have Scale 10 Superb Strength Giants and Scale 10 Terrible Strength Giants. Unlike Strength, though, it is not recommended that Mass vary much within a race. If you do allow Mass to vary for an individual, it should never be worse than Mediocre or better than Good. In fact, it is far better to call Good Mass a Gift, and Mediocre Mass a fault than treat it as an attribute.
The GM may choose to separate Strength Scale from Mass Scale. This would allow Pixies of Strength Scale -6 and Mass Scale -4, for example. However, combat between two Pixies would not work the same as combat between two humans. In this case, they would have a harder time hurting each other than humans would, since their Strength Scale (ability to give out damage) is lower than their Mass Scale (ability to take damage).
This may actually be what she wants: a super-strong superhero who can dish out punishment but can’t take it can be represented by Strength Scale 10, Mass Scale 2, for example.
See also Non-human Scale in Combat.