As soon as you arrive at Professor's Workshop, he will show the kids a rocket of his own invention, thanks to which you can reach the moon, where you can find clues as to where Hamburglar has escaped. Before letting you go, however, Professor will ask you to find at least five cards of his puzzle (at this point you should already have collected two).
Level 1 - Ports o' Comets
Walk to the right, paying attention to the meteors. After jumping over the first gap, jump over the narrow blue pillars. Even if they just appear to be part of the background, you can in fact jump on them. This way, with a few long jumps to the left, you'll reach a row of blocks with five 1-Ups! Then go right and grab one of the floating blocks. Immediately after, you will find a super springboard. Thanks to the block you have collected, you can make a very high jump and reach a card in the sky: jump on it and take it. Further to the right you will find the finish line. However, you will have to take a long jump and overtake it. Below, on the right, you will find a boat. Jump into it and go through the whole level backwards, paying attention to the fish. At the end you will find a card to collect and a zipper. Enter the zipper to access a bonus area. You will notice three paths, all filled with sand to be excavated. However, there is a fourth best path. Jump to the right, past the top edge of the screen. You will thus find a hidden path. Digging the sand beneath you, you'll come to a spot where there are three 1-Ups! Then collect the arches and enter the zipper to return to the main level. You will find yourself at the beginning of the level. Cross it again, as you did before, until you reach the finish line.
The first card you found is for CosMc's Retreat and the second is a secret card!
Level 2 - Dino Dunes
A convoluted level. Proceed to the right and dig through the loose ground, the same way as when grabbing the blocks. At the top right there is also a 1-Up. Down in the cave, continue to the right until you notice a fill-in block on a platform. Grab it and return to the beginning of the level. Place the fill-in block in the dotted platform and climb up. Go right as far as you can and dig through the ground to reach some arches. Then go back and completely dig the ground under the platform with the spinner. In the lower tunnel, however, be careful to leave a few squares of sand at regular intervals, as if they were steps. When you are done, go back to the platform with the spinner and use it to flip over. Thanks to the steps you have created, you will be able to reach the cave below upside down, where you can take a card and a 1-Up, using the springboards. Then return to the spinner to straighten up. Go back to where you got the fill-in block and go right. Digging the ground below you can take many arches. There are also two other 1-Ups at the bottom left. Continue to the right to exit the cave. Climb the platforms to the right and jump to the blocks on the left, ignoring the spinner for now. On the left you can climb over the top edge of the screen and reach an area with many arches. Go back and this time use the spinner to flip over. You can then take the arches under the blocks and go to the right of the finish line, where you will find another spinner to straighten up, before crossing the finish line.
The card you found is for Professor's Workshop.
Level 3 - Magic Forest
Walk to the right. You will come to what looks like a finish line with arches on it. It is actually a false finish line, which however will immediately get you out of the level, so take a long jump and cross it. Keep going until you find a fill-in block on a branch. Grab it and return to the beginning of the level. Place the fill-in block in the dotted platform and use it to climb up. Proceed to the right jumping on the trunks, until you reach a zipper. Go in. You'll find yourself above where you got the fill-in block. Jump on the leaf and to the right, against the trunk, you will find a card to collect. Then continue to the right to reach the real finish line. There are no paths to cross it and take you to the right of it, but if you take a run and take a long jump you can still do it.
The card you found is for Professor's Workshop.
Level 4 - Desert Cove
In the sand below you there is a 1-Up at the top left, take it. Digging the loose soil to the right you will find another one, in the bottom left corner. Take this too, but be careful not to fall. The bottom of this level is in fact made up of a lake in which the Gnash fish swims. Descend carefully and proceed to the right. To proceed, you will need to dig more sand barriers. You will come to a point where there are bones suspended in the void. You will have to jump on these bones very carefully, because if you stay on the same bone for a while, it will fall. You will have to go to the top right, where you will find a card to collect. Then carefully drop down and continue to the right, jumping over other bones. After a short climb, proceed to the left. You will find a boat in a pool of water. Instead of jumping into it, grab it quickly. Then go back to where the bones are and throw the boat into the lake. You can thus safely cross this large pool of water, up to the left end. Here you will find a zipper. Enter it and you will find yourself in another area of the level. On the right there is another sandy area to dig, where you will find another 1-Up, while on the left you will find another card. Take it and you will fall just to the right of the finish line.
The first card you found is for Professor’s Workshop and the second is a secret card!
Level 5 - Captain's Ship
Jump off the left edge of the ship. You will find a platform with a 1-Up to collect. Then grab the block and use the super springboard to return to the ship's deck. Then proceed to the right, climbing the masts. At the top of the fourth mast you will find a card, which you can reach with a series of long jumps. Alternatively, immediately after the fourth mast you can drop into the water and swim quickly to the left, to get to a platform with arches to collect and a zipper. The zipper will transport you to the top of the masts, making it easier to reach the card but in this way you risk being bitten by Gnash, who is waiting for you in the water. After getting the card, go right. When you get to a mast with two arches on each side, drop down to reach a small platform with two blocks. Pick up on one and continue to the right, jumping across the platforms. You will come to a super springboard, which you can use thanks to the block. This will bring you to the right of the finish line, where you will also find another card to collect.
Both of the cards you found are for Professor's Workshop.
At this point you will have all six of Professor's cards. Go back to where the rocket is and Professor, as promised, will send you to the moon.
Note: If you go back to Professor's house (you can do this via the rocket), he will build a shortcut between his world and Ronald's, as a reward for finding all of his cards.