The ClueFinders 3rd Grade Adventures: Mystery of Mathra is the first game in the ClueFinders series. It was released in 1998.
Animals have been mysteriously disappearing from the Numerian rainforest, and rumors say that an ancient monster named Mathra has returned. Dr. Horace Pythagoras, a scientist who has traveled there to study the secrets of Numeria, believes that there should be a more logical explanation to the situation. However, while conducting his research, he was seemingly been kidnapped by the monster one day during his research. Dr. Pythagoras' last request before his abduction was to call the ClueFinders, a group of detectives founded by Dr. Pythagoras' niece, Joni Savage.
The ClueFinders travel to the rainforest in an airpline piloted by a man named Mr. Limburger, who explains the myth of Mathra to them. Legend had it that the ancient Numerian people encountered a monster named Mathra, who terrorized the animals of the forest. They eventually captured Mathra and locked him in a deep dungeon. Afraid that Mathra might escape, they fled their city and locked the entrance with a golden key, which they split into two halves. The halves of the key were then buried deep in puzzles in two corners of the forest, in hopes that this would only allow the wise and worthy to enter the city.
The ClueFinders conclude that they need find the two pieces of the key and get to the Lost City. Just then, Dr. Pythragoras' computer companion, LapTrap, appears to assist the ClueFinders. LapTrap explains that Dr. Pythagoras recorded the location of the two key pieces and the Lost City on a map inside of one of LapTrap's programs. Joni and Santiago set out to explore the rainforest, while Leslie and Owen remain at the camp to provide backup via Santiago's video phone.
The two areas of the rainforest that contain the keys are the Monkey Kingdom and the Goo Lagoon. During their travels, the ClueFinders meet highly intelligent talking animals and plants who have valuable information on how to find the keys to the lost city. By helping out the creatures of the forest, the ClueFinders are able to obtain items required to complete the ancient Numerian puzzles: Sneezeberries from the Monkey Kingdom, and Goo Beetles from the Goo Lagoon. Both locations also contain clues that suggest that Mathra couldn't be behind the animals' disappearance: a business card labeled "Fletcher's Furriers", and a can of aviation engine oil.
After Joni and Santiago collect both key halves, Mr. Limburger offers to fly them to the Lost City. However, when they jump out of the plane with their parachutes, they land in the jungle canopy, far from the Lost City. The ClueFinders eventually make their way on their own to the Lost City's gates. When they take out both keys, they fuse together to form one key, which they then use to unlock the gate.
Inside, they find what appears to be Mathra sleeping, but then it occurs to them (having collected the evidence on their quest to find the keys) who is really behind the animals' disappearance — Mr. Limburger. Limburger built a disguise for his airplane, so it would appear to be Mathra, having used the legend of Mathra to provide a cover of his smuggling of animal hides for his fur company. He reveals that he kidnapped Dr. Pythagoras because he felt that Dr. Pythagoras was too close to exposing the smuggling operations, and is now being held captive with the animals that Limburger captured. After admitting that he was behind the mystery, Limburger locks Joni, Santiago, and LapTrap in the city and flies away in his Mathra plane to collect more animals.
Then two ancient guardians of the Lost City, which take the form of stone statues, reveal to the ClueFinders that Dr. Pythagoras and the captured animals are trapped on the other side of the Bottomless Pits of Doom. In order to save them, the ClueFinders must rebuild an ancient Mathra trap created by the Numerians long ago, by collecting snakes made from ancient Numerian magnets called Snagnets. After they do so, the Mathra trap becomes invisible, and the Cluefinders lure the returning Limburger to fly his plane into it. Upon falling into the trap, Limburger's plane drops into the pits.
As the ClueFinders leave the rainforest by boat, Dr. Pythagoras gives them LapTrap as a reward for them for saving the rainforest. LapTrap faints when he hears he'll be going on more dangerous adventures with them, as the forest creatures that the ClueFinders helped wave goodbye to them in the distance. Meanwhile, Limburger reappears in the rainforest, having survived the plunge on the bottomless pits. He swears his vengeance against the Cluefinders, and as he walks away with his dark mood unappeased, the real Mathra appears behind him, roars, and breathes fire.
- Joni Savage
- Santiago Rivera
- Owen Lam
- Leslie Clark
- Dr. Horace Pythagoras
- Fletcher Q. Limburger
- Vasco de Bongo
- Queen Itchybella
- Monument Monkey
- Chest Monkey
- Door Monkey
- Vine Monkey
- Antonio the Guard Monkey
- Twin Spiders
- Yellow Matter
- Goo Creature
- Spit Spot
Locations and ActivitiesEdit
Monkey Kingdom (Math)Edit
- Address Stones
- Gameplay: Place the address stones in the grooves on the monkey's doorway to create a number that fits his requirement.
- Skill(s) Taught: Place value
- Items Earned: Purple sneezeberries
- Gameplay: Read the inscription on the monument. Then click and drag the correct plaque to the empty space.
- Skill(s) Taught: Word problems
- Items Earned: Blue sneezeberries
- The Pit and the Vines
- Gameplay: Find the vine that fits the pit's perimeter.
- Skill(s) Taught: Perimeter
- Items Earned: Red sneezeberries
- The Queen's Calendar
- Gameplay: Read the clues, then place the marker on the correct date on the queen's calendar.
- Skill(s) Taught: Deductive reasoning with numbers
- Items Earned: Gold sneezeberries
- Treasure Chest
- Gameplay: Place the correct amount of money in the treasure chest.
- Skill(s) Taught: Addition with money
- Items Earned: Green sneezeberries
- Chasm of Snakes
- Gameplay: Find the correct set of stones that balances out the bridge.
- Skills Taught: Addition with whole numbers or decimals
- The Rings of Fire
- Skill(s) Taught: Addition, subtraction, multiplication, division
- Items Earned: A key to the lost city
- Items Required: Sneezeberries (One color per bridge)
Goo Lagoon (Logic)Edit
- The Spider Sisters
- Gameplay: Look at the two bugs on the first sister's plate. Then click and drag a bug the other sister's plate, so that her bugs go together in a similar way as her sister's.
- Skill(s) Taught: Graphic analogies
- Items Earned: Purple beetle bag
- Crabalock Attack
- Gameplay: Look at the top two words and deduce how they go together. Find the key that goes with the bottom word in a similar way.
- Skill(s) Taught: Word analogies
- Items Earned: Blue beetle bag
- Gameplay: Carefully look at the designs on the leaves, and find the one that is different from the rest.
- Skill(s) Taught: Visual thinking
- Items Earned: Red beetle bag
- Moths and Fleas
- Gameplay: Find the creature that fits the description.
- Skill(s) Taught: Attributes
- Items Earned: Gold beetle bag
- Worms' Day Out
- Gameplay: Read the directions on the sign, and then place the worms in the correctly numbered seats.
- Skill(s) Taught: Deductive reasoning with story problems
- Items Earned: Green beetle bag
- River of the Goo Creature
- Gameplay: Look at the bridge pieces to deduce the pattern. Then drag bridge pieces to complete the pattern and fill in the gap.
- Skill(s) Taught: Patterns
- The Walls of Goo Falls
- Skill(s) Taught: Logical reasoning
- Items Earned: A key to the lost city
- Items Required: Beetle Bags (One color per wall)
Jungle Canopy (Geography)Edit
- Where Are You?
- Gameplay: Use the hints to find out where you are on the map, then place the marker on that spot.
- Skill(s) Taught: Map skills
- Birds on Vacation
- Gameplay: Use the hints to figure out which U.S. state each bird wants to go to.
- Skill(s) Taught: United States geography
Lost City (Science and Language Arts)Edit
- The Chamber of Order
- Skill(s) Taught: Classification
- Items Earned: Purple snagnets
- The Chamber of Vision
- Skill(s) Taught: Sequencing
- Items Earned: Gold snagnets
- The Chamber of Structure
- Skill(s) Taught: Constructing animal skeletons
- Items Earned: Red snagnets
- The Chamber of Illusion
- Skill(s) Taught: Making inferences
- Items Earned: Blue snagnets
- The Chamber of Knowledge
- Skill(s) Taught: Reading for main ideas
- Items Earned: Green snagnets
- The Bottomless Pits of Doom
- Skill(s) Taught: Antonyms, synonyms, categories, homophones, parts of speech
- Items Required: Snagnets (One color per bridge)
- This is the only ClueFinders game to feature full song sequences.
- This is also the only ClueFinders game to have different music play during the title sequence, as well as the only one to have three full-fledged stages (The Monkey Kingdom, Goo Lagoon, and the Lost City)
- Some of the animations for Joni and Santiago in this game was reused in The ClueFinders 5th Grade Adventures: Secret of the Living Volcano.