Noise is generated per-present, and combined additively for each child. Under ordinary circumstances:

• Blum-Bloopers produce 6 Noise.
• Fum-Foozlers produce 8 Noise for girls, 4 for boys.
• Who-Whonkers produce 5 Noise for girls, 9 for boys.
• Sloo-Slonkers produce 5 Noise, plus 1 extra unit for every two years since birth.
• Gah-Ginkas produce 5 Noise, plus 1 extra unit for every two years until teenagerhood.
• Trum-Troopas usually produce 10 Noise, but occasionally only produce 5. (Figuring out what if anything predicts a halving here is the main unsolved problem in my analysis.)

Each child has exactly one gift type which produces twice as much Noise as it would by default. This remains consistent over a child’s life (or at least until adolescence), so we can use past preferences to predict how they’ll react this year.

(I haven’t confirmed this is literally optimal given my model but I bet it’s pretty close)

Andy: F + G

Betty: W + G

Sally: W + T

Phoebe: W + T

Freddie: F + B 

Eddie: F + B

Cindy: B + T

Mary: W + S

Ollie: S + B

Johnny: F + S

Andy: S + B

Betty: F + B

Sally: F + S

Phoebe: G + B

Freddie: S + T

Eddie: W + T

Cindy: W + T

Mary: G + F

Ollie: F + W

Johnny: B + W

I suspect the convention the Whos think is best,

Is a lesson, a puzzle, a trick and a test.

I doubt that they’re stupid, or that they don’t care:

It’s how they teach children to trade and to share.

As a rule, the traditions your ancestors used,

Should not be ignored. But they can be improved!

The dice may choose poorly. I know that I won’t.

So, each child gets gifts: one they like, one they don’t.

That way, I make sure that no Who is left out,

Of the joy or the dealing this day is about.

Andy: F + B

Betty: S + B

Sally: G + S

Phoebe: F + B

Freddie: W + T

Eddie: S + T

Cindy: G + T

Mary: W + F

Ollie: B + W

Johnny: F + W

And as for myself, well, it’s hard to believe

That I missed this solution: I’ll simply just . . . leave!

Flee south for the winter! Head back when it’s done!

Let them have all their joys, all their noise, all their fun!

(If I so disapprove of how Whos spend this day,

I shouldn’t own property here anyway!)

blum: 6
fum: 8(F), 4(M)
gah: 11-age/2
sloo: 5+age/2
trum: 5
who: 5(F), 9(M)

Everyone has one non-trum toy that produces double-noise, for them, regardless of age.
trum produces double-noise if someone else in your family also received a trum this year.

Give sloo to young, gah to old, who to female, fum to male, and trum to separate families. Do not give doublers.

e.g. [doubler | give them these]
Andy Sue Who 12 M 1550 sloo | gah fum
Betty Drew Who 11 F 1551 fum | gah who
Sally Sue Who 11 F 1552 fum | who trum 
Phoebe Drew Who 9 F 1553 sloo | who blum
Freddie Lou Who 8 M 1554 sloo | fum trum
Eddie Sue Who 8 M 1555 who | fum blum
Cindy Drew Who 6 F 1556 who | trum blum
Mary Lou Who 6 F 1557 gah | sloo who
Ollie Lou Who 5 M 1558 fum | sloo blum
Johnny Drew Who 4 M 1559 blum | sloo fum 
 

I noticed that the B/F/W combinations tended to be consistent when given to the same child multiple times, so looked at these first.

Assuming that noise is a summed contribution from both toys, then it looks like B usually contributes 6, with some discrepancies consistent with it sometimes contributing 12 instead.

F meanwhile always contributes 4, 8 or 16.

amd W contributes 5(only if F is 8 or 16), 9 (only if F is 4 or 8), 10 (only if F is 8), or 18 (seen with F=4).

Note: it is always possible to make such an attribution with 3 variables, regardless if it really is a sum, but it seems to have worked out in view of subsequent results.

Next, I looked at T, combinations with which seem to be inconsistent but not so as to suggest an age relationship. It looks like T is for some whos 5 or 10 (inconsistently) and for other 10 or 20 (inconsistently).

G and S vary usually from about 5-11 (Note - I wrote this before finding the numbers for the latest Whos!), with G dropping by 1 every 2nd year, and S rising by one every second year for any particular Who.

Comparing to actual recent results we can fill in expectations for how much noise our current Whos will make next year with different toys:

Who | B | F | G | S | T | W

1550 Andy Sue | 6 | 4 | 5 | 18 22 | 5 or 10 | 9

1551 Betty Drew | 6 | 16 | 11 | 10 |5 or 10 | 5

1552 Sally Sue |  6 | 16 |  6 |  10 |  ? 5 or 10 | 5

1553 Phoebe Drew | 6 | 8 | 7 | 18 | ? 5 or 10 | 5

1554 Freddie Lou | ? 6 |  4 |  7 |  17 |  5 or 10 | 9

1555 Eddie Sue | 6 | 4 |  7 | 9 | ? | ?  9 or 18

1556 Cindy Drew | 6 | 8 | 8 |  8 | ? 5 or 10 | 10

1557 Mary Lou |  ? 6 | 8 | 19 16 | 8 | 5 or 10 | ? 5

1558 Ollie Lou | ? |  8 |  8 or 9 | 7 | ? | 9

1559 Johnny Drew | 12 | 4 | ? |  7 | ? 5 or 10 | 9

And whoops, looks like something's wrong since Andy Sue  had a huge jump in noise from toy combos including Sloo-Slonkers between the ages of 3 and 4, looking like he enjoys S to the tune of 14 noise at age 4 and 16 at 7. Something's also up with Phoebe Drew. But, I continued to project forwards in both cases to 18 at the current year anyway as if nothing is wrong.

Also something wrong with Mary Lou and Gah-Ginkas, again I press forward assuming it's all OK.

While we have seen combos with Sally Sue, Phoebe Drew, Eddie Sue, Cindy Drew, Ollie Lou and johnny Drew involving Trum-Troopas, they've all had a 10 contribution from T, so we don't know if they get 5/10 or 10/20 from them.

Now for the solutions:

we have 4B, 4F, 2G, 3S, 3T and 4W to distribute.

In order to try to maximize noise, I'll distribute as follows:

1550 Andy Sue  S + W 

1551 Betty Drew  F + G

1552 Sally Sue  F + T

1553 Phoebe Drew   F + S + T

1554 Freddie Lou B + S   

1555 Eddie Sue F + T + W

1556 Cindy Drew F+ W 

1557 Mary Lou B+ G

1558 Ollie Lou B+ W T

1559 Johnny Drew B+ W

In order to try to minimize noise, I'll distribute as follows:

1550 Andy Sue  F + G T

1551 Betty Drew  B + W 

1552 Sally Sue  B + W

1553 Phoebe Drew B + W

1554 Freddie Lou  F + T

1555 Eddie Sue F + G 

1556 Cindy Drew B + S

1557 Mary Lou T + W 

1558 Ollie Lou  G + S + T 

1559 Johnny Drew  F + S

edit: in view of abstractapplic's observations, we can fill in some of the ?'s in the chart, added in above. The information that a doubling is involved with the anomalies also changes how we project forward the high Gs or Ss. This also led me to reinterpret some results above, also I noticed I had accidentally projected upwards instead of down for G for Mary Lou. Whoops. Since we don't know what Ollie Lou has doubled, I've now avoided giving him T when minimizing noise, even at the expense of a less optimal G allocation. Also fishing for more upside when maximizing noise.

Min noise in 9 max is 32, with an average of 16.
Everyone with > 28 noise had a Trum-Troopa. All the really low instances of noise which involved Trum-Troops were wither with a boy paired with a Fum-Foozler or a girl pared with a Who-Whonker.

Girls tend to make much more noise with Fum-Foozler than boys.

There seems to be a slight bias to younger children producing less noise with Sloo-Slonker.

If a child likes/dislikes a Gah-Ginka one year it looks like it will also like/dislike it another year.

Blum-Blooper appears to be consistently unpopular with Fum-Foozler and normally unpopular with Who-Whonker

Which suggests.

Blum-Blooper: Ideally goes with Fum-Foozler but possibly also Who-Wonker.
Fum-Foozler: Only goes to boys
Gah-Ginka: Goes to children that haven't liked it in previous years.
Sloo-Slonker: Give to younger children
Trun-Troops: Go to either boys with a Fum-Foozler or girls with a Who-Whonker
Who-Whonker: From others

   Four Blum-Bloopers
   Four Fum-Foozlers
   Two Gah-Ginkas
   Three Sloo-Slonkers
   Three Trum-Troopas
   Four Who-Whonkers

Andy Sue Who 12 M  Gah-Ginka, Blum-Blooper
Betty Drew Who 11 F Trun-Troops, Who-Whonker
Sally Sue Who 11 F Trun-Troops, Who-Whonker
Phoebe Drew Who 9 F Trun-Troops, Who-Whonker
Freddie Lou Who 8 M Fum-Foozler, Blum-Blooper
Eddie Sue Who 8 M Gah-Ginka, Fum-Foozler
Cindy Drew Who 6 F Blum-Blooper, Who-Whonker
Mary Lou Who 6 F Sloo-Slonker, Blum-Blooper
Ollie Lou Who 5 M Fum-Foozler, Sloo-Slonker
Johnny Drew Who 4 M Fum-Foozler, Sloo-Slonker

Girls with a Blum-Blooper make 6 Noise.

Girls with a Who-Whonker make 5 or 10 Noise.

Girls with a Fum-Foozler make 8 or 16 Noise.

Boys with a Blum-Blooper make 6 or 12 Noise.

Boys with a Who-Whonker make 9 or 18 Noise.

Boys with a Fum-Foozler make 4 or 8 Noise.

Sloo-Sloonkers make 4+ceiling((1+Age)/2) Noise, except sometimes you give them to boys and they make more.

Gah-Ginkas make 4+ceiling((14-Age)/2) Noise, except sometimes you give them to girls and they make more.

Trum-Troopas are hard to predict but there are a lot of 5s and 10s in that distribution and the average is pretty high.

Though I haven't quite confirmed this yet, it looks like children who react unusually to a given present one Christmas (doubled Who-Whonker Noise, bonus Sloo-Slonker Noise, etc) tend to react the same way on subsequent Christmases. If that's true, it means my next step should be researching the noise history of the individual Whos I'm targeting.