There are four solutions to this level:

Arrange so that the shape of the bites match up:
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Arrange so that the shapes of the food match (circle, square, and octagon):
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Put the food with seeds together, the food with holes together, and the solid food together:

There are five solutions to this level:

Arrange by length of fork:
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Arrange by legnth of prong:
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Arrange by number of scallops on the handles:
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Arrange by amount of rust:
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Arrange by length of handles with wooden handle being on one side, and metal on the other:

There are four solutions to this level:

Arrange by shape of mug:
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Arrange by shape of handles with the handles alternating between left and right:
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Arrange by colour and pattern on the mug, making a fluid shape:
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Arrange by following the patterns of the lines on the mugs:

There are four solutions to this level:

Make it so that all the corn are showing the peppered side:
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Make it so that the corn is showing the eaten side:
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Create an wave shape with the black corn:
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Create a descending pattern with the eaten corn:
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There are three solutions to this level:

Place the leaves in the tan lines:
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Place the leaves where the ink drops fit in the leave's holes:
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Use the pen outlines for the bigger leaves then stack the other leaves on top, loosely based on shape:
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Drop the two vases to break them. Then using the broken pieces, fix the larger middle vase:

There are five solutions to this level:

Put the toys in order as they are morphing into the bird shape:
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Arrange so that the height of the screens are in ascending/descending order:
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Arrange so that the length of the chains are in ascending/descending order:
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Arrange in order of button roundness:
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Press the buttons on each toy and count how many times you need to press until the animal on the screen is asleep. Then put the toys in order from most to least presses:
(Thank you HYPERED1!)

Pack the electronics into the box like in the image below:
Make sure the VHS tape pattern is correct, the cell phones are in decending order, and the labels on the cassette tapes are in ascending or descending order.

There are three solutions to this level:

Arrange the balls from biggest to smallest:
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You can lift up and bounce the balls. Put them in order from most to least bouncy:
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Count the segments on the balls. Put them in order from most to least segments:

There are four solutions to this level:

Put the cubes with the strawberries in one glass, the mint in another, and the berries in the third:
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Put the ice in the glasses in order of how many cubes there are:
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Organise the ice in the middle glass so that the ice cracks match up:
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Arrange the ice so that the water level in all glasses are equal:

There are four solutions to this level:

Put the same type of topping on each slice:
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Evenly distribute the toppings to each slice:
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Remove all of the toppings so that there's only cheese:
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Put the meat toppings on one half of the pizza and the veg on the other half:

There are five solutions to this level:

Organise the containers so that the labels are completed:
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Organise by the colour of the lids:
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In the first column, put the almost empty containers, in the second, put the half full, and in the third, put the full containers:
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Put the containers in order of the tab on the lid moving from right to left:
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Put the containers in ascending order based on the contents (so 5 veg, 4 liquids, 3 pasta etc.):

Make sure that you are centring the containers or else it won't count.

Move the windows to create the same pattern across the middle of all three window panes:

There are five solutions to this level:

Put the cacti in the correct vase based on the ascending amount of flowers:
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Put the pots and cacti in ascending order of height:
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Put the pots in ascending order of height but the cacti in order so that they are the same height:
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Put the pots in order of how many lines there are, and put the cacti in order of how many sections they have:
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Put the pots in order of ascending height of the bevel at the bottom of the pot and put the cacti in ascending order of the length of root:

Place the origami pieces on the board like a jigsaw:

There are four solutions to this level:

Match the shapes on the wings to the holes in the wool stitching:
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If you click on the moths, they will flutter their wings revealing their striped bodies:
















Put the moths in a clockwise ascending order based on the amount of stripes on the body:













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Put the moths in a clockwise ascending order based on the amount of stitches represented on the wings:
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Put the moths in a clockwise ascending order based on how many times the moths flutter their wing when you click on them:

There are two solutions to this level:

Put all of the equipment in the tin:
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Put all of the equipment on the table:

HEADS UP: Make sure that you click on the small quarter circle protractor so that it becomes a half circle!

There are two solutions to this level:

Arrange the jars so that the pattern of the ink spill matches:
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Arrange the jars so that the labels are complete:

Put the objects in the drawers based on plastic, nature, glass, wood, and metal:

Pull on the different sections of the curtain until the pattern matches:

There are five solutions to this level:

Stack the books based on the placement of the bookmarks:
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Stack the books so that the swirl pattern on the cover matches:
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Stack the books based on the placement of the ridges on the spine:
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On the first pile stack the books with images of full things, on the second stack, piles books with images of half full things, and on the third stack, pile books with images of empty things:
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Stack all of the books on top of each other but make sure that the black covers are the only ones that you can see:

Make sure that you are stacking the books from biggest to smallest.

Store all of the items in the drawer:
Make sure to get the three stickers on the lint roller.

There are three solutions to this level:

Group the bells by shape and put them in order of size:
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Group the bells by design (square, diamond, circle) and put them in order of design size:
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Group the bells by handle types (hoop, figure, and simple long) and put them in order of size:

There are three solutions to this level:

Put the pieces in the middle section like a puzzle:
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Organise the pieces by colour:
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Organise the pieces by character type:

There are three solutions to this level:

Group the book by colour:
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Group the book by spine design and put them in order to create the design:
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Group the books by size:

Just throw the toys around. With each toy, a set of eyes will appear.

There are two solutions to this level:

Both solutions involve putting the objects away but there are different options depending on if you interact with the object:
Layout 1:
Layout 2:

Put the objects in the drawer:

There a couple of objects you have to interact with. Make sure the accordion is pulled out so that it fits the compartment, activate the music box so that the handle fits in the gap, and push on the handle of the slide whistle so that it fits in the gap.

There are two solutions to this level:

Put the combs in the drawer:
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Put the combs on the table, use the grain to help you place them:

Put the supplies in the first aid kit:

There are two solutions to this level:

Put the robots in the packaging, there are two layouts:

Layout 1:
(Thank you oldladygreybun for the screenshot!)
Layout 2:

This level has a series of puzzles.

Thank you to adam55502 for letting me know that "For 32, all three solutions/stars have to be done in one go. Personally, I did not do this originally and thus did not get the 100% achievement even will all the stars."

First, create a design using the glass pieces:
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Then put the compasses in ascending order of spikes on the compass design:
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Then put the compasses in order of detail on the face (n, n and s, n and s and e and w etc.):
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Move the compasses around until they're all facing North:
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Create a new design with the glass:
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Match the holes in the keys to the design on the locks:
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Match the shape of the key wards to the shackle:
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Put the keys in descending and ascending order based on key length:
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Create a final design with the glass peices:
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Open the switch blades by putting the little metal notch at the bottom in the correct pattern:
(Thank you ThePockyAddict!)
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Put the switchblades in ascending and descending order:
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Move the switchblades around until they fit together:
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There's also a section at the end where you must fight the cat for the star. It will then break and you have to put the pieces together again and put the star in the centre of the screen.

You need 50 stars to unlock.

There are two solutions to this level:

Create 3 bread slice outlines using colour as a guide:
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Create a big plus with the crusts:

You need 60 stars to unlock.

There are three solutions to this level:

Put in order of height (case line, frosting, and candle):
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Put the case, frosting, and candle together based on colour:
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Put the case, frosting, and candle together based on the amount of detail:

You need 70 stars to unlock.

There are three solutions:

There are 2 shelves to put the markers on so for the first solution, on the top shelf create a gradient from black to white. On the bottom shelf, create a rainbow pattern.
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Half of the markers and lids have vertical stripes on the bottom and top and the other half have horizontal stripes near the middle. Pair the markers with the corresponding lid, then place them in numerical order:
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Half of the markers and lids have a pointed marker tip and the other half have a slanted marker tip. Pair the markers with the corresponding lid, then place the markers in ascending then descending order:

You need 80 stars to unlock.

There are five solutions to this level:

Use the outlines to place the whistles:
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Group the whistles by colour then place them in order of hole height:
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Group the whistles by shapes. Order the long thin whistles by height, the cone whistles by pointiness, the double whistles by how tapered they are, and the ridged whistles by the amount of ridges:
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Group the whistles by hole shape and order them as if the whistles are turning:
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Group the whistles by chain colour and order them from 1-5 links:

You need 90 stars to unlock.

There will be a bunch of scenes, you just need to select a certain object in each scene to get the cat.
The objects in order are:
Paper bag
Jar with black contents
Book
Picture
Yarn
Lamp
Wellington boot
Umbrella

Thank you for checking out my guide! ♡